These changes are the raw update to linux-4.4.6-rt14. Kernel sources

are taken from kernel.org, and rt patch from the rt wiki download page.

During the rebasing, the following patch collided:

Force tick interrupt and get rid of softirq magic(I70131fb85).

Collisions have been removed because its logic was found on the
source already.

Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

40 files changed, 7123 insertions, 0 deletions

diff --git a/kernel/arch/x86/entry/Makefile b/kernel/arch/x86/entry/Makefile
new file mode 100644
index 000000000..bd55dedd7
--- /dev/null
+++ b/kernel/arch/x86/entry/Makefile
@@ -0,0 +1,11 @@
+#
+# Makefile for the x86 low level entry code
+#
+obj-y				:= entry_$(BITS).o thunk_$(BITS).o syscall_$(BITS).o
+obj-y				+= common.o
+
+obj-y				+= vdso/
+obj-y				+= vsyscall/
+
+obj-$(CONFIG_IA32_EMULATION)	+= entry_64_compat.o syscall_32.o
+
diff --git a/kernel/arch/x86/entry/calling.h b/kernel/arch/x86/entry/calling.h
new file mode 100644
index 000000000..3c71dd947
--- /dev/null
+++ b/kernel/arch/x86/entry/calling.h
@@ -0,0 +1,234 @@
+/*
+
+ x86 function call convention, 64-bit:
+ -------------------------------------
+  arguments           |  callee-saved      | extra caller-saved | return
+ [callee-clobbered]   |                    | [callee-clobbered] |
+ ---------------------------------------------------------------------------
+ rdi rsi rdx rcx r8-9 | rbx rbp [*] r12-15 | r10-11             | rax, rdx [**]
+
+ ( rsp is obviously invariant across normal function calls. (gcc can 'merge'
+   functions when it sees tail-call optimization possibilities) rflags is
+   clobbered. Leftover arguments are passed over the stack frame.)
+
+ [*]  In the frame-pointers case rbp is fixed to the stack frame.
+
+ [**] for struct return values wider than 64 bits the return convention is a
+      bit more complex: up to 128 bits width we return small structures
+      straight in rax, rdx. For structures larger than that (3 words or
+      larger) the caller puts a pointer to an on-stack return struct
+      [allocated in the caller's stack frame] into the first argument - i.e.
+      into rdi. All other arguments shift up by one in this case.
+      Fortunately this case is rare in the kernel.
+
+For 32-bit we have the following conventions - kernel is built with
+-mregparm=3 and -freg-struct-return:
+
+ x86 function calling convention, 32-bit:
+ ----------------------------------------
+  arguments         | callee-saved        | extra caller-saved | return
+ [callee-clobbered] |                     | [callee-clobbered] |
+ -------------------------------------------------------------------------
+ eax edx ecx        | ebx edi esi ebp [*] | <none>             | eax, edx [**]
+
+ ( here too esp is obviously invariant across normal function calls. eflags
+   is clobbered. Leftover arguments are passed over the stack frame. )
+
+ [*]  In the frame-pointers case ebp is fixed to the stack frame.
+
+ [**] We build with -freg-struct-return, which on 32-bit means similar
+      semantics as on 64-bit: edx can be used for a second return value
+      (i.e. covering integer and structure sizes up to 64 bits) - after that
+      it gets more complex and more expensive: 3-word or larger struct returns
+      get done in the caller's frame and the pointer to the return struct goes
+      into regparm0, i.e. eax - the other arguments shift up and the
+      function's register parameters degenerate to regparm=2 in essence.
+
+*/
+
+#ifdef CONFIG_X86_64
+
+/*
+ * 64-bit system call stack frame layout defines and helpers,
+ * for assembly code:
+ */
+
+/* The layout forms the "struct pt_regs" on the stack: */
+/*
+ * C ABI says these regs are callee-preserved. They aren't saved on kernel entry
+ * unless syscall needs a complete, fully filled "struct pt_regs".
+ */
+#define R15		0*8
+#define R14		1*8
+#define R13		2*8
+#define R12		3*8
+#define RBP		4*8
+#define RBX		5*8
+/* These regs are callee-clobbered. Always saved on kernel entry. */
+#define R11		6*8
+#define R10		7*8
+#define R9		8*8
+#define R8		9*8
+#define RAX		10*8
+#define RCX		11*8
+#define RDX		12*8
+#define RSI		13*8
+#define RDI		14*8
+/*
+ * On syscall entry, this is syscall#. On CPU exception, this is error code.
+ * On hw interrupt, it's IRQ number:
+ */
+#define ORIG_RAX	15*8
+/* Return frame for iretq */
+#define RIP		16*8
+#define CS		17*8
+#define EFLAGS		18*8
+#define RSP		19*8
+#define SS		20*8
+
+#define SIZEOF_PTREGS	21*8
+
+	.macro ALLOC_PT_GPREGS_ON_STACK addskip=0
+	addq	$-(15*8+\addskip), %rsp
+	.endm
+
+	.macro SAVE_C_REGS_HELPER offset=0 rax=1 rcx=1 r8910=1 r11=1
+	.if \r11
+	movq %r11, 6*8+\offset(%rsp)
+	.endif
+	.if \r8910
+	movq %r10, 7*8+\offset(%rsp)
+	movq %r9,  8*8+\offset(%rsp)
+	movq %r8,  9*8+\offset(%rsp)
+	.endif
+	.if \rax
+	movq %rax, 10*8+\offset(%rsp)
+	.endif
+	.if \rcx
+	movq %rcx, 11*8+\offset(%rsp)
+	.endif
+	movq %rdx, 12*8+\offset(%rsp)
+	movq %rsi, 13*8+\offset(%rsp)
+	movq %rdi, 14*8+\offset(%rsp)
+	.endm
+	.macro SAVE_C_REGS offset=0
+	SAVE_C_REGS_HELPER \offset, 1, 1, 1, 1
+	.endm
+	.macro SAVE_C_REGS_EXCEPT_RAX_RCX offset=0
+	SAVE_C_REGS_HELPER \offset, 0, 0, 1, 1
+	.endm
+	.macro SAVE_C_REGS_EXCEPT_R891011
+	SAVE_C_REGS_HELPER 0, 1, 1, 0, 0
+	.endm
+	.macro SAVE_C_REGS_EXCEPT_RCX_R891011
+	SAVE_C_REGS_HELPER 0, 1, 0, 0, 0
+	.endm
+	.macro SAVE_C_REGS_EXCEPT_RAX_RCX_R11
+	SAVE_C_REGS_HELPER 0, 0, 0, 1, 0
+	.endm
+
+	.macro SAVE_EXTRA_REGS offset=0
+	movq %r15, 0*8+\offset(%rsp)
+	movq %r14, 1*8+\offset(%rsp)
+	movq %r13, 2*8+\offset(%rsp)
+	movq %r12, 3*8+\offset(%rsp)
+	movq %rbp, 4*8+\offset(%rsp)
+	movq %rbx, 5*8+\offset(%rsp)
+	.endm
+
+	.macro RESTORE_EXTRA_REGS offset=0
+	movq 0*8+\offset(%rsp), %r15
+	movq 1*8+\offset(%rsp), %r14
+	movq 2*8+\offset(%rsp), %r13
+	movq 3*8+\offset(%rsp), %r12
+	movq 4*8+\offset(%rsp), %rbp
+	movq 5*8+\offset(%rsp), %rbx
+	.endm
+
+	.macro ZERO_EXTRA_REGS
+	xorl	%r15d, %r15d
+	xorl	%r14d, %r14d
+	xorl	%r13d, %r13d
+	xorl	%r12d, %r12d
+	xorl	%ebp, %ebp
+	xorl	%ebx, %ebx
+	.endm
+
+	.macro RESTORE_C_REGS_HELPER rstor_rax=1, rstor_rcx=1, rstor_r11=1, rstor_r8910=1, rstor_rdx=1
+	.if \rstor_r11
+	movq 6*8(%rsp), %r11
+	.endif
+	.if \rstor_r8910
+	movq 7*8(%rsp), %r10
+	movq 8*8(%rsp), %r9
+	movq 9*8(%rsp), %r8
+	.endif
+	.if \rstor_rax
+	movq 10*8(%rsp), %rax
+	.endif
+	.if \rstor_rcx
+	movq 11*8(%rsp), %rcx
+	.endif
+	.if \rstor_rdx
+	movq 12*8(%rsp), %rdx
+	.endif
+	movq 13*8(%rsp), %rsi
+	movq 14*8(%rsp), %rdi
+	.endm
+	.macro RESTORE_C_REGS
+	RESTORE_C_REGS_HELPER 1,1,1,1,1
+	.endm
+	.macro RESTORE_C_REGS_EXCEPT_RAX
+	RESTORE_C_REGS_HELPER 0,1,1,1,1
+	.endm
+	.macro RESTORE_C_REGS_EXCEPT_RCX
+	RESTORE_C_REGS_HELPER 1,0,1,1,1
+	.endm
+	.macro RESTORE_C_REGS_EXCEPT_R11
+	RESTORE_C_REGS_HELPER 1,1,0,1,1
+	.endm
+	.macro RESTORE_C_REGS_EXCEPT_RCX_R11
+	RESTORE_C_REGS_HELPER 1,0,0,1,1
+	.endm
+
+	.macro REMOVE_PT_GPREGS_FROM_STACK addskip=0
+	subq $-(15*8+\addskip), %rsp
+	.endm
+
+	.macro icebp
+	.byte 0xf1
+	.endm
+
+#else /* CONFIG_X86_64 */
+
+/*
+ * For 32bit only simplified versions of SAVE_ALL/RESTORE_ALL. These
+ * are different from the entry_32.S versions in not changing the segment
+ * registers. So only suitable for in kernel use, not when transitioning
+ * from or to user space. The resulting stack frame is not a standard
+ * pt_regs frame. The main use case is calling C code from assembler
+ * when all the registers need to be preserved.
+ */
+
+	.macro SAVE_ALL
+	pushl %eax
+	pushl %ebp
+	pushl %edi
+	pushl %esi
+	pushl %edx
+	pushl %ecx
+	pushl %ebx
+	.endm
+
+	.macro RESTORE_ALL
+	popl %ebx
+	popl %ecx
+	popl %edx
+	popl %esi
+	popl %edi
+	popl %ebp
+	popl %eax
+	.endm
+
+#endif /* CONFIG_X86_64 */
+
diff --git a/kernel/arch/x86/entry/common.c b/kernel/arch/x86/entry/common.c
new file mode 100644
index 000000000..3ec240f39
--- /dev/null
+++ b/kernel/arch/x86/entry/common.c
@@ -0,0 +1,493 @@
+/*
+ * common.c - C code for kernel entry and exit
+ * Copyright (c) 2015 Andrew Lutomirski
+ * GPL v2
+ *
+ * Based on asm and ptrace code by many authors.  The code here originated
+ * in ptrace.c and signal.c.
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/tracehook.h>
+#include <linux/audit.h>
+#include <linux/seccomp.h>
+#include <linux/signal.h>
+#include <linux/export.h>
+#include <linux/context_tracking.h>
+#include <linux/user-return-notifier.h>
+#include <linux/uprobes.h>
+
+#include <asm/desc.h>
+#include <asm/traps.h>
+#include <asm/vdso.h>
+#include <asm/uaccess.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
+static struct thread_info *pt_regs_to_thread_info(struct pt_regs *regs)
+{
+	unsigned long top_of_stack =
+		(unsigned long)(regs + 1) + TOP_OF_KERNEL_STACK_PADDING;
+	return (struct thread_info *)(top_of_stack - THREAD_SIZE);
+}
+
+#ifdef CONFIG_CONTEXT_TRACKING
+/* Called on entry from user mode with IRQs off. */
+__visible void enter_from_user_mode(void)
+{
+	CT_WARN_ON(ct_state() != CONTEXT_USER);
+	user_exit();
+}
+#endif
+
+static void do_audit_syscall_entry(struct pt_regs *regs, u32 arch)
+{
+#ifdef CONFIG_X86_64
+	if (arch == AUDIT_ARCH_X86_64) {
+		audit_syscall_entry(regs->orig_ax, regs->di,
+				    regs->si, regs->dx, regs->r10);
+	} else
+#endif
+	{
+		audit_syscall_entry(regs->orig_ax, regs->bx,
+				    regs->cx, regs->dx, regs->si);
+	}
+}
+
+/*
+ * We can return 0 to resume the syscall or anything else to go to phase
+ * 2.  If we resume the syscall, we need to put something appropriate in
+ * regs->orig_ax.
+ *
+ * NB: We don't have full pt_regs here, but regs->orig_ax and regs->ax
+ * are fully functional.
+ *
+ * For phase 2's benefit, our return value is:
+ * 0:			resume the syscall
+ * 1:			go to phase 2; no seccomp phase 2 needed
+ * anything else:	go to phase 2; pass return value to seccomp
+ */
+unsigned long syscall_trace_enter_phase1(struct pt_regs *regs, u32 arch)
+{
+	struct thread_info *ti = pt_regs_to_thread_info(regs);
+	unsigned long ret = 0;
+	u32 work;
+
+	if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
+		BUG_ON(regs != task_pt_regs(current));
+
+	work = ACCESS_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY;
+
+#ifdef CONFIG_CONTEXT_TRACKING
+	/*
+	 * If TIF_NOHZ is set, we are required to call user_exit() before
+	 * doing anything that could touch RCU.
+	 */
+	if (work & _TIF_NOHZ) {
+		enter_from_user_mode();
+		work &= ~_TIF_NOHZ;
+	}
+#endif
+
+#ifdef CONFIG_SECCOMP
+	/*
+	 * Do seccomp first -- it should minimize exposure of other
+	 * code, and keeping seccomp fast is probably more valuable
+	 * than the rest of this.
+	 */
+	if (work & _TIF_SECCOMP) {
+		struct seccomp_data sd;
+
+		sd.arch = arch;
+		sd.nr = regs->orig_ax;
+		sd.instruction_pointer = regs->ip;
+#ifdef CONFIG_X86_64
+		if (arch == AUDIT_ARCH_X86_64) {
+			sd.args[0] = regs->di;
+			sd.args[1] = regs->si;
+			sd.args[2] = regs->dx;
+			sd.args[3] = regs->r10;
+			sd.args[4] = regs->r8;
+			sd.args[5] = regs->r9;
+		} else
+#endif
+		{
+			sd.args[0] = regs->bx;
+			sd.args[1] = regs->cx;
+			sd.args[2] = regs->dx;
+			sd.args[3] = regs->si;
+			sd.args[4] = regs->di;
+			sd.args[5] = regs->bp;
+		}
+
+		BUILD_BUG_ON(SECCOMP_PHASE1_OK != 0);
+		BUILD_BUG_ON(SECCOMP_PHASE1_SKIP != 1);
+
+		ret = seccomp_phase1(&sd);
+		if (ret == SECCOMP_PHASE1_SKIP) {
+			regs->orig_ax = -1;
+			ret = 0;
+		} else if (ret != SECCOMP_PHASE1_OK) {
+			return ret;  /* Go directly to phase 2 */
+		}
+
+		work &= ~_TIF_SECCOMP;
+	}
+#endif
+
+	/* Do our best to finish without phase 2. */
+	if (work == 0)
+		return ret;  /* seccomp and/or nohz only (ret == 0 here) */
+
+#ifdef CONFIG_AUDITSYSCALL
+	if (work == _TIF_SYSCALL_AUDIT) {
+		/*
+		 * If there is no more work to be done except auditing,
+		 * then audit in phase 1.  Phase 2 always audits, so, if
+		 * we audit here, then we can't go on to phase 2.
+		 */
+		do_audit_syscall_entry(regs, arch);
+		return 0;
+	}
+#endif
+
+	return 1;  /* Something is enabled that we can't handle in phase 1 */
+}
+
+/* Returns the syscall nr to run (which should match regs->orig_ax). */
+long syscall_trace_enter_phase2(struct pt_regs *regs, u32 arch,
+				unsigned long phase1_result)
+{
+	struct thread_info *ti = pt_regs_to_thread_info(regs);
+	long ret = 0;
+	u32 work = ACCESS_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY;
+
+	if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
+		BUG_ON(regs != task_pt_regs(current));
+
+	/*
+	 * If we stepped into a sysenter/syscall insn, it trapped in
+	 * kernel mode; do_debug() cleared TF and set TIF_SINGLESTEP.
+	 * If user-mode had set TF itself, then it's still clear from
+	 * do_debug() and we need to set it again to restore the user
+	 * state.  If we entered on the slow path, TF was already set.
+	 */
+	if (work & _TIF_SINGLESTEP)
+		regs->flags |= X86_EFLAGS_TF;
+
+#ifdef CONFIG_SECCOMP
+	/*
+	 * Call seccomp_phase2 before running the other hooks so that
+	 * they can see any changes made by a seccomp tracer.
+	 */
+	if (phase1_result > 1 && seccomp_phase2(phase1_result)) {
+		/* seccomp failures shouldn't expose any additional code. */
+		return -1;
+	}
+#endif
+
+	if (unlikely(work & _TIF_SYSCALL_EMU))
+		ret = -1L;
+
+	if ((ret || test_thread_flag(TIF_SYSCALL_TRACE)) &&
+	    tracehook_report_syscall_entry(regs))
+		ret = -1L;
+
+	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
+		trace_sys_enter(regs, regs->orig_ax);
+
+	do_audit_syscall_entry(regs, arch);
+
+	return ret ?: regs->orig_ax;
+}
+
+long syscall_trace_enter(struct pt_regs *regs)
+{
+	u32 arch = is_ia32_task() ? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64;
+	unsigned long phase1_result = syscall_trace_enter_phase1(regs, arch);
+
+	if (phase1_result == 0)
+		return regs->orig_ax;
+	else
+		return syscall_trace_enter_phase2(regs, arch, phase1_result);
+}
+
+#define EXIT_TO_USERMODE_LOOP_FLAGS				\
+	(_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE |	\
+	 _TIF_NEED_RESCHED_MASK | _TIF_USER_RETURN_NOTIFY)
+
+static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags)
+{
+	/*
+	 * In order to return to user mode, we need to have IRQs off with
+	 * none of _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_USER_RETURN_NOTIFY,
+	 * _TIF_UPROBE, or _TIF_NEED_RESCHED set.  Several of these flags
+	 * can be set at any time on preemptable kernels if we have IRQs on,
+	 * so we need to loop.  Disabling preemption wouldn't help: doing the
+	 * work to clear some of the flags can sleep.
+	 */
+	while (true) {
+		/* We have work to do. */
+		local_irq_enable();
+
+		if (cached_flags & _TIF_NEED_RESCHED_MASK)
+			schedule();
+
+#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
+		if (unlikely(current->forced_info.si_signo)) {
+			struct task_struct *t = current;
+			force_sig_info(t->forced_info.si_signo, &t->forced_info, t);
+			t->forced_info.si_signo = 0;
+		}
+#endif
+		if (cached_flags & _TIF_UPROBE)
+			uprobe_notify_resume(regs);
+
+		/* deal with pending signal delivery */
+		if (cached_flags & _TIF_SIGPENDING)
+			do_signal(regs);
+
+		if (cached_flags & _TIF_NOTIFY_RESUME) {
+			clear_thread_flag(TIF_NOTIFY_RESUME);
+			tracehook_notify_resume(regs);
+		}
+
+		if (cached_flags & _TIF_USER_RETURN_NOTIFY)
+			fire_user_return_notifiers();
+
+		/* Disable IRQs and retry */
+		local_irq_disable();
+
+		cached_flags = READ_ONCE(pt_regs_to_thread_info(regs)->flags);
+
+		if (!(cached_flags & EXIT_TO_USERMODE_LOOP_FLAGS))
+			break;
+
+	}
+}
+
+/* Called with IRQs disabled. */
+__visible inline void prepare_exit_to_usermode(struct pt_regs *regs)
+{
+	u32 cached_flags;
+
+	if (IS_ENABLED(CONFIG_PROVE_LOCKING) && WARN_ON(!irqs_disabled()))
+		local_irq_disable();
+
+	lockdep_sys_exit();
+
+	cached_flags =
+		READ_ONCE(pt_regs_to_thread_info(regs)->flags);
+
+	if (unlikely(cached_flags & EXIT_TO_USERMODE_LOOP_FLAGS))
+		exit_to_usermode_loop(regs, cached_flags);
+
+	user_enter();
+}
+
+#define SYSCALL_EXIT_WORK_FLAGS				\
+	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT |	\
+	 _TIF_SINGLESTEP | _TIF_SYSCALL_TRACEPOINT)
+
+static void syscall_slow_exit_work(struct pt_regs *regs, u32 cached_flags)
+{
+	bool step;
+
+	audit_syscall_exit(regs);
+
+	if (cached_flags & _TIF_SYSCALL_TRACEPOINT)
+		trace_sys_exit(regs, regs->ax);
+
+	/*
+	 * If TIF_SYSCALL_EMU is set, we only get here because of
+	 * TIF_SINGLESTEP (i.e. this is PTRACE_SYSEMU_SINGLESTEP).
+	 * We already reported this syscall instruction in
+	 * syscall_trace_enter().
+	 */
+	step = unlikely(
+		(cached_flags & (_TIF_SINGLESTEP | _TIF_SYSCALL_EMU))
+		== _TIF_SINGLESTEP);
+	if (step || cached_flags & _TIF_SYSCALL_TRACE)
+		tracehook_report_syscall_exit(regs, step);
+}
+
+/*
+ * Called with IRQs on and fully valid regs.  Returns with IRQs off in a
+ * state such that we can immediately switch to user mode.
+ */
+__visible inline void syscall_return_slowpath(struct pt_regs *regs)
+{
+	struct thread_info *ti = pt_regs_to_thread_info(regs);
+	u32 cached_flags = READ_ONCE(ti->flags);
+
+	CT_WARN_ON(ct_state() != CONTEXT_KERNEL);
+
+	if (IS_ENABLED(CONFIG_PROVE_LOCKING) &&
+	    WARN(irqs_disabled(), "syscall %ld left IRQs disabled", regs->orig_ax))
+		local_irq_enable();
+
+	/*
+	 * First do one-time work.  If these work items are enabled, we
+	 * want to run them exactly once per syscall exit with IRQs on.
+	 */
+	if (unlikely(cached_flags & SYSCALL_EXIT_WORK_FLAGS))
+		syscall_slow_exit_work(regs, cached_flags);
+
+#ifdef CONFIG_COMPAT
+	/*
+	 * Compat syscalls set TS_COMPAT.  Make sure we clear it before
+	 * returning to user mode.
+	 */
+	ti->status &= ~TS_COMPAT;
+#endif
+
+	local_irq_disable();
+	prepare_exit_to_usermode(regs);
+}
+
+#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
+/*
+ * Does a 32-bit syscall.  Called with IRQs on and does all entry and
+ * exit work and returns with IRQs off.  This function is extremely hot
+ * in workloads that use it, and it's usually called from
+ * do_fast_syscall_32, so forcibly inline it to improve performance.
+ */
+#ifdef CONFIG_X86_32
+/* 32-bit kernels use a trap gate for INT80, and the asm code calls here. */
+__visible
+#else
+/* 64-bit kernels use do_syscall_32_irqs_off() instead. */
+static
+#endif
+__always_inline void do_syscall_32_irqs_on(struct pt_regs *regs)
+{
+	struct thread_info *ti = pt_regs_to_thread_info(regs);
+	unsigned int nr = (unsigned int)regs->orig_ax;
+
+#ifdef CONFIG_IA32_EMULATION
+	ti->status |= TS_COMPAT;
+#endif
+
+	if (READ_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY) {
+		/*
+		 * Subtlety here: if ptrace pokes something larger than
+		 * 2^32-1 into orig_ax, this truncates it.  This may or
+		 * may not be necessary, but it matches the old asm
+		 * behavior.
+		 */
+		nr = syscall_trace_enter(regs);
+	}
+
+	if (likely(nr < IA32_NR_syscalls)) {
+		/*
+		 * It's possible that a 32-bit syscall implementation
+		 * takes a 64-bit parameter but nonetheless assumes that
+		 * the high bits are zero.  Make sure we zero-extend all
+		 * of the args.
+		 */
+		regs->ax = ia32_sys_call_table[nr](
+			(unsigned int)regs->bx, (unsigned int)regs->cx,
+			(unsigned int)regs->dx, (unsigned int)regs->si,
+			(unsigned int)regs->di, (unsigned int)regs->bp);
+	}
+
+	syscall_return_slowpath(regs);
+}
+
+#ifdef CONFIG_X86_64
+/* Handles INT80 on 64-bit kernels */
+__visible void do_syscall_32_irqs_off(struct pt_regs *regs)
+{
+	local_irq_enable();
+	do_syscall_32_irqs_on(regs);
+}
+#endif
+
+/* Returns 0 to return using IRET or 1 to return using SYSEXIT/SYSRETL. */
+__visible long do_fast_syscall_32(struct pt_regs *regs)
+{
+	/*
+	 * Called using the internal vDSO SYSENTER/SYSCALL32 calling
+	 * convention.  Adjust regs so it looks like we entered using int80.
+	 */
+
+	unsigned long landing_pad = (unsigned long)current->mm->context.vdso +
+		vdso_image_32.sym_int80_landing_pad;
+
+	/*
+	 * SYSENTER loses EIP, and even SYSCALL32 needs us to skip forward
+	 * so that 'regs->ip -= 2' lands back on an int $0x80 instruction.
+	 * Fix it up.
+	 */
+	regs->ip = landing_pad;
+
+	/*
+	 * Fetch EBP from where the vDSO stashed it.
+	 *
+	 * WARNING: We are in CONTEXT_USER and RCU isn't paying attention!
+	 */
+	local_irq_enable();
+	if (
+#ifdef CONFIG_X86_64
+		/*
+		 * Micro-optimization: the pointer we're following is explicitly
+		 * 32 bits, so it can't be out of range.
+		 */
+		__get_user(*(u32 *)&regs->bp,
+			    (u32 __user __force *)(unsigned long)(u32)regs->sp)
+#else
+		get_user(*(u32 *)&regs->bp,
+			 (u32 __user __force *)(unsigned long)(u32)regs->sp)
+#endif
+		) {
+
+		/* User code screwed up. */
+		local_irq_disable();
+		regs->ax = -EFAULT;
+#ifdef CONFIG_CONTEXT_TRACKING
+		enter_from_user_mode();
+#endif
+		prepare_exit_to_usermode(regs);
+		return 0;	/* Keep it simple: use IRET. */
+	}
+
+	/* Now this is just like a normal syscall. */
+	do_syscall_32_irqs_on(regs);
+
+#ifdef CONFIG_X86_64
+	/*
+	 * Opportunistic SYSRETL: if possible, try to return using SYSRETL.
+	 * SYSRETL is available on all 64-bit CPUs, so we don't need to
+	 * bother with SYSEXIT.
+	 *
+	 * Unlike 64-bit opportunistic SYSRET, we can't check that CX == IP,
+	 * because the ECX fixup above will ensure that this is essentially
+	 * never the case.
+	 */
+	return regs->cs == __USER32_CS && regs->ss == __USER_DS &&
+		regs->ip == landing_pad &&
+		(regs->flags & (X86_EFLAGS_RF | X86_EFLAGS_TF)) == 0;
+#else
+	/*
+	 * Opportunistic SYSEXIT: if possible, try to return using SYSEXIT.
+	 *
+	 * Unlike 64-bit opportunistic SYSRET, we can't check that CX == IP,
+	 * because the ECX fixup above will ensure that this is essentially
+	 * never the case.
+	 *
+	 * We don't allow syscalls at all from VM86 mode, but we still
+	 * need to check VM, because we might be returning from sys_vm86.
+	 */
+	return static_cpu_has(X86_FEATURE_SEP) &&
+		regs->cs == __USER_CS && regs->ss == __USER_DS &&
+		regs->ip == landing_pad &&
+		(regs->flags & (X86_EFLAGS_RF | X86_EFLAGS_TF | X86_EFLAGS_VM)) == 0;
+#endif
+}
+#endif
diff --git a/kernel/arch/x86/entry/entry_32.S b/kernel/arch/x86/entry/entry_32.S
new file mode 100644
index 000000000..2d722ee01
--- /dev/null
+++ b/kernel/arch/x86/entry/entry_32.S
@@ -0,0 +1,1097 @@
+/*
+ *  Copyright (C) 1991,1992  Linus Torvalds
+ *
+ * entry_32.S contains the system-call and low-level fault and trap handling routines.
+ *
+ * Stack layout while running C code:
+ *	ptrace needs to have all registers on the stack.
+ *	If the order here is changed, it needs to be
+ *	updated in fork.c:copy_process(), signal.c:do_signal(),
+ *	ptrace.c and ptrace.h
+ *
+ *	 0(%esp) - %ebx
+ *	 4(%esp) - %ecx
+ *	 8(%esp) - %edx
+ *	 C(%esp) - %esi
+ *	10(%esp) - %edi
+ *	14(%esp) - %ebp
+ *	18(%esp) - %eax
+ *	1C(%esp) - %ds
+ *	20(%esp) - %es
+ *	24(%esp) - %fs
+ *	28(%esp) - %gs		saved iff !CONFIG_X86_32_LAZY_GS
+ *	2C(%esp) - orig_eax
+ *	30(%esp) - %eip
+ *	34(%esp) - %cs
+ *	38(%esp) - %eflags
+ *	3C(%esp) - %oldesp
+ *	40(%esp) - %oldss
+ */
+
+#include <linux/linkage.h>
+#include <linux/err.h>
+#include <asm/thread_info.h>
+#include <asm/irqflags.h>
+#include <asm/errno.h>
+#include <asm/segment.h>
+#include <asm/smp.h>
+#include <asm/page_types.h>
+#include <asm/percpu.h>
+#include <asm/processor-flags.h>
+#include <asm/ftrace.h>
+#include <asm/irq_vectors.h>
+#include <asm/cpufeature.h>
+#include <asm/alternative-asm.h>
+#include <asm/asm.h>
+#include <asm/smap.h>
+
+	.section .entry.text, "ax"
+
+/*
+ * We use macros for low-level operations which need to be overridden
+ * for paravirtualization.  The following will never clobber any registers:
+ *   INTERRUPT_RETURN (aka. "iret")
+ *   GET_CR0_INTO_EAX (aka. "movl %cr0, %eax")
+ *   ENABLE_INTERRUPTS_SYSEXIT (aka "sti; sysexit").
+ *
+ * For DISABLE_INTERRUPTS/ENABLE_INTERRUPTS (aka "cli"/"sti"), you must
+ * specify what registers can be overwritten (CLBR_NONE, CLBR_EAX/EDX/ECX/ANY).
+ * Allowing a register to be clobbered can shrink the paravirt replacement
+ * enough to patch inline, increasing performance.
+ */
+
+#ifdef CONFIG_PREEMPT
+# define preempt_stop(clobbers)	DISABLE_INTERRUPTS(clobbers); TRACE_IRQS_OFF
+#else
+# define preempt_stop(clobbers)
+# define resume_kernel		restore_all
+#endif
+
+.macro TRACE_IRQS_IRET
+#ifdef CONFIG_TRACE_IRQFLAGS
+	testl	$X86_EFLAGS_IF, PT_EFLAGS(%esp)     # interrupts off?
+	jz	1f
+	TRACE_IRQS_ON
+1:
+#endif
+.endm
+
+/*
+ * User gs save/restore
+ *
+ * %gs is used for userland TLS and kernel only uses it for stack
+ * canary which is required to be at %gs:20 by gcc.  Read the comment
+ * at the top of stackprotector.h for more info.
+ *
+ * Local labels 98 and 99 are used.
+ */
+#ifdef CONFIG_X86_32_LAZY_GS
+
+ /* unfortunately push/pop can't be no-op */
+.macro PUSH_GS
+	pushl	$0
+.endm
+.macro POP_GS pop=0
+	addl	$(4 + \pop), %esp
+.endm
+.macro POP_GS_EX
+.endm
+
+ /* all the rest are no-op */
+.macro PTGS_TO_GS
+.endm
+.macro PTGS_TO_GS_EX
+.endm
+.macro GS_TO_REG reg
+.endm
+.macro REG_TO_PTGS reg
+.endm
+.macro SET_KERNEL_GS reg
+.endm
+
+#else	/* CONFIG_X86_32_LAZY_GS */
+
+.macro PUSH_GS
+	pushl	%gs
+.endm
+
+.macro POP_GS pop=0
+98:	popl	%gs
+  .if \pop <> 0
+	add	$\pop, %esp
+  .endif
+.endm
+.macro POP_GS_EX
+.pushsection .fixup, "ax"
+99:	movl	$0, (%esp)
+	jmp	98b
+.popsection
+	_ASM_EXTABLE(98b, 99b)
+.endm
+
+.macro PTGS_TO_GS
+98:	mov	PT_GS(%esp), %gs
+.endm
+.macro PTGS_TO_GS_EX
+.pushsection .fixup, "ax"
+99:	movl	$0, PT_GS(%esp)
+	jmp	98b
+.popsection
+	_ASM_EXTABLE(98b, 99b)
+.endm
+
+.macro GS_TO_REG reg
+	movl	%gs, \reg
+.endm
+.macro REG_TO_PTGS reg
+	movl	\reg, PT_GS(%esp)
+.endm
+.macro SET_KERNEL_GS reg
+	movl	$(__KERNEL_STACK_CANARY), \reg
+	movl	\reg, %gs
+.endm
+
+#endif /* CONFIG_X86_32_LAZY_GS */
+
+.macro SAVE_ALL pt_regs_ax=%eax
+	cld
+	PUSH_GS
+	pushl	%fs
+	pushl	%es
+	pushl	%ds
+	pushl	\pt_regs_ax
+	pushl	%ebp
+	pushl	%edi
+	pushl	%esi
+	pushl	%edx
+	pushl	%ecx
+	pushl	%ebx
+	movl	$(__USER_DS), %edx
+	movl	%edx, %ds
+	movl	%edx, %es
+	movl	$(__KERNEL_PERCPU), %edx
+	movl	%edx, %fs
+	SET_KERNEL_GS %edx
+.endm
+
+.macro RESTORE_INT_REGS
+	popl	%ebx
+	popl	%ecx
+	popl	%edx
+	popl	%esi
+	popl	%edi
+	popl	%ebp
+	popl	%eax
+.endm
+
+.macro RESTORE_REGS pop=0
+	RESTORE_INT_REGS
+1:	popl	%ds
+2:	popl	%es
+3:	popl	%fs
+	POP_GS \pop
+.pushsection .fixup, "ax"
+4:	movl	$0, (%esp)
+	jmp	1b
+5:	movl	$0, (%esp)
+	jmp	2b
+6:	movl	$0, (%esp)
+	jmp	3b
+.popsection
+	_ASM_EXTABLE(1b, 4b)
+	_ASM_EXTABLE(2b, 5b)
+	_ASM_EXTABLE(3b, 6b)
+	POP_GS_EX
+.endm
+
+ENTRY(ret_from_fork)
+	pushl	%eax
+	call	schedule_tail
+	GET_THREAD_INFO(%ebp)
+	popl	%eax
+	pushl	$0x0202				# Reset kernel eflags
+	popfl
+
+	/* When we fork, we trace the syscall return in the child, too. */
+	movl    %esp, %eax
+	call    syscall_return_slowpath
+	jmp     restore_all
+END(ret_from_fork)
+
+ENTRY(ret_from_kernel_thread)
+	pushl	%eax
+	call	schedule_tail
+	GET_THREAD_INFO(%ebp)
+	popl	%eax
+	pushl	$0x0202				# Reset kernel eflags
+	popfl
+	movl	PT_EBP(%esp), %eax
+	call	*PT_EBX(%esp)
+	movl	$0, PT_EAX(%esp)
+
+	/*
+	 * Kernel threads return to userspace as if returning from a syscall.
+	 * We should check whether anything actually uses this path and, if so,
+	 * consider switching it over to ret_from_fork.
+	 */
+	movl    %esp, %eax
+	call    syscall_return_slowpath
+	jmp     restore_all
+ENDPROC(ret_from_kernel_thread)
+
+/*
+ * Return to user mode is not as complex as all this looks,
+ * but we want the default path for a system call return to
+ * go as quickly as possible which is why some of this is
+ * less clear than it otherwise should be.
+ */
+
+	# userspace resumption stub bypassing syscall exit tracing
+	ALIGN
+ret_from_exception:
+	preempt_stop(CLBR_ANY)
+ret_from_intr:
+	GET_THREAD_INFO(%ebp)
+#ifdef CONFIG_VM86
+	movl	PT_EFLAGS(%esp), %eax		# mix EFLAGS and CS
+	movb	PT_CS(%esp), %al
+	andl	$(X86_EFLAGS_VM | SEGMENT_RPL_MASK), %eax
+#else
+	/*
+	 * We can be coming here from child spawned by kernel_thread().
+	 */
+	movl	PT_CS(%esp), %eax
+	andl	$SEGMENT_RPL_MASK, %eax
+#endif
+	cmpl	$USER_RPL, %eax
+	jb	resume_kernel			# not returning to v8086 or userspace
+
+ENTRY(resume_userspace)
+	DISABLE_INTERRUPTS(CLBR_ANY)
+	TRACE_IRQS_OFF
+	movl	%esp, %eax
+	call	prepare_exit_to_usermode
+	jmp	restore_all
+END(ret_from_exception)
+
+#ifdef CONFIG_PREEMPT
+ENTRY(resume_kernel)
+	DISABLE_INTERRUPTS(CLBR_ANY)
+need_resched:
+	# preempt count == 0 + NEED_RS set?
+	cmpl	$0, PER_CPU_VAR(__preempt_count)
+#ifndef CONFIG_PREEMPT_LAZY
+	jnz	restore_all
+#else
+	jz test_int_off
+
+	# atleast preempt count == 0 ?
+	cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count)
+	jne restore_all
+
+	cmpl $0,TI_preempt_lazy_count(%ebp)	# non-zero preempt_lazy_count ?
+	jnz restore_all
+
+	testl $_TIF_NEED_RESCHED_LAZY, TI_flags(%ebp)
+	jz restore_all
+test_int_off:
+#endif
+	testl	$X86_EFLAGS_IF, PT_EFLAGS(%esp)	# interrupts off (exception path) ?
+	jz	restore_all
+	call	preempt_schedule_irq
+	jmp	need_resched
+END(resume_kernel)
+#endif
+
+	# SYSENTER  call handler stub
+ENTRY(entry_SYSENTER_32)
+	movl	TSS_sysenter_sp0(%esp), %esp
+sysenter_past_esp:
+	pushl	$__USER_DS		/* pt_regs->ss */
+	pushl	%ebp			/* pt_regs->sp (stashed in bp) */
+	pushfl				/* pt_regs->flags (except IF = 0) */
+	orl	$X86_EFLAGS_IF, (%esp)	/* Fix IF */
+	pushl	$__USER_CS		/* pt_regs->cs */
+	pushl	$0			/* pt_regs->ip = 0 (placeholder) */
+	pushl	%eax			/* pt_regs->orig_ax */
+	SAVE_ALL pt_regs_ax=$-ENOSYS	/* save rest */
+
+	/*
+	 * User mode is traced as though IRQs are on, and SYSENTER
+	 * turned them off.
+	 */
+	TRACE_IRQS_OFF
+
+	movl	%esp, %eax
+	call	do_fast_syscall_32
+	/* XEN PV guests always use IRET path */
+	ALTERNATIVE "testl %eax, %eax; jz .Lsyscall_32_done", \
+		    "jmp .Lsyscall_32_done", X86_FEATURE_XENPV
+
+/* Opportunistic SYSEXIT */
+	TRACE_IRQS_ON			/* User mode traces as IRQs on. */
+	movl	PT_EIP(%esp), %edx	/* pt_regs->ip */
+	movl	PT_OLDESP(%esp), %ecx	/* pt_regs->sp */
+1:	mov	PT_FS(%esp), %fs
+	PTGS_TO_GS
+	popl	%ebx			/* pt_regs->bx */
+	addl	$2*4, %esp		/* skip pt_regs->cx and pt_regs->dx */
+	popl	%esi			/* pt_regs->si */
+	popl	%edi			/* pt_regs->di */
+	popl	%ebp			/* pt_regs->bp */
+	popl	%eax			/* pt_regs->ax */
+
+	/*
+	 * Return back to the vDSO, which will pop ecx and edx.
+	 * Don't bother with DS and ES (they already contain __USER_DS).
+	 */
+	ENABLE_INTERRUPTS_SYSEXIT
+
+.pushsection .fixup, "ax"
+2:	movl	$0, PT_FS(%esp)
+	jmp	1b
+.popsection
+	_ASM_EXTABLE(1b, 2b)
+	PTGS_TO_GS_EX
+ENDPROC(entry_SYSENTER_32)
+
+	# system call handler stub
+ENTRY(entry_INT80_32)
+	ASM_CLAC
+	pushl	%eax			/* pt_regs->orig_ax */
+	SAVE_ALL pt_regs_ax=$-ENOSYS	/* save rest */
+
+	/*
+	 * User mode is traced as though IRQs are on.  Unlike the 64-bit
+	 * case, INT80 is a trap gate on 32-bit kernels, so interrupts
+	 * are already on (unless user code is messing around with iopl).
+	 */
+
+	movl	%esp, %eax
+	call	do_syscall_32_irqs_on
+.Lsyscall_32_done:
+
+restore_all:
+	TRACE_IRQS_IRET
+restore_all_notrace:
+#ifdef CONFIG_X86_ESPFIX32
+	movl	PT_EFLAGS(%esp), %eax		# mix EFLAGS, SS and CS
+	/*
+	 * Warning: PT_OLDSS(%esp) contains the wrong/random values if we
+	 * are returning to the kernel.
+	 * See comments in process.c:copy_thread() for details.
+	 */
+	movb	PT_OLDSS(%esp), %ah
+	movb	PT_CS(%esp), %al
+	andl	$(X86_EFLAGS_VM | (SEGMENT_TI_MASK << 8) | SEGMENT_RPL_MASK), %eax
+	cmpl	$((SEGMENT_LDT << 8) | USER_RPL), %eax
+	je ldt_ss				# returning to user-space with LDT SS
+#endif
+restore_nocheck:
+	RESTORE_REGS 4				# skip orig_eax/error_code
+irq_return:
+	INTERRUPT_RETURN
+.section .fixup, "ax"
+ENTRY(iret_exc	)
+	pushl	$0				# no error code
+	pushl	$do_iret_error
+	jmp	error_code
+.previous
+	_ASM_EXTABLE(irq_return, iret_exc)
+
+#ifdef CONFIG_X86_ESPFIX32
+ldt_ss:
+#ifdef CONFIG_PARAVIRT
+	/*
+	 * The kernel can't run on a non-flat stack if paravirt mode
+	 * is active.  Rather than try to fixup the high bits of
+	 * ESP, bypass this code entirely.  This may break DOSemu
+	 * and/or Wine support in a paravirt VM, although the option
+	 * is still available to implement the setting of the high
+	 * 16-bits in the INTERRUPT_RETURN paravirt-op.
+	 */
+	cmpl	$0, pv_info+PARAVIRT_enabled
+	jne	restore_nocheck
+#endif
+
+/*
+ * Setup and switch to ESPFIX stack
+ *
+ * We're returning to userspace with a 16 bit stack. The CPU will not
+ * restore the high word of ESP for us on executing iret... This is an
+ * "official" bug of all the x86-compatible CPUs, which we can work
+ * around to make dosemu and wine happy. We do this by preloading the
+ * high word of ESP with the high word of the userspace ESP while
+ * compensating for the offset by changing to the ESPFIX segment with
+ * a base address that matches for the difference.
+ */
+#define GDT_ESPFIX_SS PER_CPU_VAR(gdt_page) + (GDT_ENTRY_ESPFIX_SS * 8)
+	mov	%esp, %edx			/* load kernel esp */
+	mov	PT_OLDESP(%esp), %eax		/* load userspace esp */
+	mov	%dx, %ax			/* eax: new kernel esp */
+	sub	%eax, %edx			/* offset (low word is 0) */
+	shr	$16, %edx
+	mov	%dl, GDT_ESPFIX_SS + 4		/* bits 16..23 */
+	mov	%dh, GDT_ESPFIX_SS + 7		/* bits 24..31 */
+	pushl	$__ESPFIX_SS
+	pushl	%eax				/* new kernel esp */
+	/*
+	 * Disable interrupts, but do not irqtrace this section: we
+	 * will soon execute iret and the tracer was already set to
+	 * the irqstate after the IRET:
+	 */
+	DISABLE_INTERRUPTS(CLBR_EAX)
+	lss	(%esp), %esp			/* switch to espfix segment */
+	jmp	restore_nocheck
+#endif
+ENDPROC(entry_INT80_32)
+
+.macro FIXUP_ESPFIX_STACK
+/*
+ * Switch back for ESPFIX stack to the normal zerobased stack
+ *
+ * We can't call C functions using the ESPFIX stack. This code reads
+ * the high word of the segment base from the GDT and swiches to the
+ * normal stack and adjusts ESP with the matching offset.
+ */
+#ifdef CONFIG_X86_ESPFIX32
+	/* fixup the stack */
+	mov	GDT_ESPFIX_SS + 4, %al /* bits 16..23 */
+	mov	GDT_ESPFIX_SS + 7, %ah /* bits 24..31 */
+	shl	$16, %eax
+	addl	%esp, %eax			/* the adjusted stack pointer */
+	pushl	$__KERNEL_DS
+	pushl	%eax
+	lss	(%esp), %esp			/* switch to the normal stack segment */
+#endif
+.endm
+.macro UNWIND_ESPFIX_STACK
+#ifdef CONFIG_X86_ESPFIX32
+	movl	%ss, %eax
+	/* see if on espfix stack */
+	cmpw	$__ESPFIX_SS, %ax
+	jne	27f
+	movl	$__KERNEL_DS, %eax
+	movl	%eax, %ds
+	movl	%eax, %es
+	/* switch to normal stack */
+	FIXUP_ESPFIX_STACK
+27:
+#endif
+.endm
+
+/*
+ * Build the entry stubs with some assembler magic.
+ * We pack 1 stub into every 8-byte block.
+ */
+	.align 8
+ENTRY(irq_entries_start)
+    vector=FIRST_EXTERNAL_VECTOR
+    .rept (FIRST_SYSTEM_VECTOR - FIRST_EXTERNAL_VECTOR)
+	pushl	$(~vector+0x80)			/* Note: always in signed byte range */
+    vector=vector+1
+	jmp	common_interrupt
+	.align	8
+    .endr
+END(irq_entries_start)
+
+/*
+ * the CPU automatically disables interrupts when executing an IRQ vector,
+ * so IRQ-flags tracing has to follow that:
+ */
+	.p2align CONFIG_X86_L1_CACHE_SHIFT
+common_interrupt:
+	ASM_CLAC
+	addl	$-0x80, (%esp)			/* Adjust vector into the [-256, -1] range */
+	SAVE_ALL
+	TRACE_IRQS_OFF
+	movl	%esp, %eax
+	call	do_IRQ
+	jmp	ret_from_intr
+ENDPROC(common_interrupt)
+
+#define BUILD_INTERRUPT3(name, nr, fn)	\
+ENTRY(name)				\
+	ASM_CLAC;			\
+	pushl	$~(nr);			\
+	SAVE_ALL;			\
+	TRACE_IRQS_OFF			\
+	movl	%esp, %eax;		\
+	call	fn;			\
+	jmp	ret_from_intr;		\
+ENDPROC(name)
+
+
+#ifdef CONFIG_TRACING
+# define TRACE_BUILD_INTERRUPT(name, nr)	BUILD_INTERRUPT3(trace_##name, nr, smp_trace_##name)
+#else
+# define TRACE_BUILD_INTERRUPT(name, nr)
+#endif
+
+#define BUILD_INTERRUPT(name, nr)		\
+	BUILD_INTERRUPT3(name, nr, smp_##name);	\
+	TRACE_BUILD_INTERRUPT(name, nr)
+
+/* The include is where all of the SMP etc. interrupts come from */
+#include <asm/entry_arch.h>
+
+ENTRY(coprocessor_error)
+	ASM_CLAC
+	pushl	$0
+	pushl	$do_coprocessor_error
+	jmp	error_code
+END(coprocessor_error)
+
+ENTRY(simd_coprocessor_error)
+	ASM_CLAC
+	pushl	$0
+#ifdef CONFIG_X86_INVD_BUG
+	/* AMD 486 bug: invd from userspace calls exception 19 instead of #GP */
+	ALTERNATIVE "pushl	$do_general_protection",	\
+		    "pushl	$do_simd_coprocessor_error",	\
+		    X86_FEATURE_XMM
+#else
+	pushl	$do_simd_coprocessor_error
+#endif
+	jmp	error_code
+END(simd_coprocessor_error)
+
+ENTRY(device_not_available)
+	ASM_CLAC
+	pushl	$-1				# mark this as an int
+	pushl	$do_device_not_available
+	jmp	error_code
+END(device_not_available)
+
+#ifdef CONFIG_PARAVIRT
+ENTRY(native_iret)
+	iret
+	_ASM_EXTABLE(native_iret, iret_exc)
+END(native_iret)
+
+ENTRY(native_irq_enable_sysexit)
+	sti
+	sysexit
+END(native_irq_enable_sysexit)
+#endif
+
+ENTRY(overflow)
+	ASM_CLAC
+	pushl	$0
+	pushl	$do_overflow
+	jmp	error_code
+END(overflow)
+
+ENTRY(bounds)
+	ASM_CLAC
+	pushl	$0
+	pushl	$do_bounds
+	jmp	error_code
+END(bounds)
+
+ENTRY(invalid_op)
+	ASM_CLAC
+	pushl	$0
+	pushl	$do_invalid_op
+	jmp	error_code
+END(invalid_op)
+
+ENTRY(coprocessor_segment_overrun)
+	ASM_CLAC
+	pushl	$0
+	pushl	$do_coprocessor_segment_overrun
+	jmp	error_code
+END(coprocessor_segment_overrun)
+
+ENTRY(invalid_TSS)
+	ASM_CLAC
+	pushl	$do_invalid_TSS
+	jmp	error_code
+END(invalid_TSS)
+
+ENTRY(segment_not_present)
+	ASM_CLAC
+	pushl	$do_segment_not_present
+	jmp	error_code
+END(segment_not_present)
+
+ENTRY(stack_segment)
+	ASM_CLAC
+	pushl	$do_stack_segment
+	jmp	error_code
+END(stack_segment)
+
+ENTRY(alignment_check)
+	ASM_CLAC
+	pushl	$do_alignment_check
+	jmp	error_code
+END(alignment_check)
+
+ENTRY(divide_error)
+	ASM_CLAC
+	pushl	$0				# no error code
+	pushl	$do_divide_error
+	jmp	error_code
+END(divide_error)
+
+#ifdef CONFIG_X86_MCE
+ENTRY(machine_check)
+	ASM_CLAC
+	pushl	$0
+	pushl	machine_check_vector
+	jmp	error_code
+END(machine_check)
+#endif
+
+ENTRY(spurious_interrupt_bug)
+	ASM_CLAC
+	pushl	$0
+	pushl	$do_spurious_interrupt_bug
+	jmp	error_code
+END(spurious_interrupt_bug)
+
+#ifdef CONFIG_XEN
+/*
+ * Xen doesn't set %esp to be precisely what the normal SYSENTER
+ * entry point expects, so fix it up before using the normal path.
+ */
+ENTRY(xen_sysenter_target)
+	addl	$5*4, %esp			/* remove xen-provided frame */
+	jmp	sysenter_past_esp
+
+ENTRY(xen_hypervisor_callback)
+	pushl	$-1				/* orig_ax = -1 => not a system call */
+	SAVE_ALL
+	TRACE_IRQS_OFF
+
+	/*
+	 * Check to see if we got the event in the critical
+	 * region in xen_iret_direct, after we've reenabled
+	 * events and checked for pending events.  This simulates
+	 * iret instruction's behaviour where it delivers a
+	 * pending interrupt when enabling interrupts:
+	 */
+	movl	PT_EIP(%esp), %eax
+	cmpl	$xen_iret_start_crit, %eax
+	jb	1f
+	cmpl	$xen_iret_end_crit, %eax
+	jae	1f
+
+	jmp	xen_iret_crit_fixup
+
+ENTRY(xen_do_upcall)
+1:	mov	%esp, %eax
+	call	xen_evtchn_do_upcall
+#ifndef CONFIG_PREEMPT
+	call	xen_maybe_preempt_hcall
+#endif
+	jmp	ret_from_intr
+ENDPROC(xen_hypervisor_callback)
+
+/*
+ * Hypervisor uses this for application faults while it executes.
+ * We get here for two reasons:
+ *  1. Fault while reloading DS, ES, FS or GS
+ *  2. Fault while executing IRET
+ * Category 1 we fix up by reattempting the load, and zeroing the segment
+ * register if the load fails.
+ * Category 2 we fix up by jumping to do_iret_error. We cannot use the
+ * normal Linux return path in this case because if we use the IRET hypercall
+ * to pop the stack frame we end up in an infinite loop of failsafe callbacks.
+ * We distinguish between categories by maintaining a status value in EAX.
+ */
+ENTRY(xen_failsafe_callback)
+	pushl	%eax
+	movl	$1, %eax
+1:	mov	4(%esp), %ds
+2:	mov	8(%esp), %es
+3:	mov	12(%esp), %fs
+4:	mov	16(%esp), %gs
+	/* EAX == 0 => Category 1 (Bad segment)
+	   EAX != 0 => Category 2 (Bad IRET) */
+	testl	%eax, %eax
+	popl	%eax
+	lea	16(%esp), %esp
+	jz	5f
+	jmp	iret_exc
+5:	pushl	$-1				/* orig_ax = -1 => not a system call */
+	SAVE_ALL
+	jmp	ret_from_exception
+
+.section .fixup, "ax"
+6:	xorl	%eax, %eax
+	movl	%eax, 4(%esp)
+	jmp	1b
+7:	xorl	%eax, %eax
+	movl	%eax, 8(%esp)
+	jmp	2b
+8:	xorl	%eax, %eax
+	movl	%eax, 12(%esp)
+	jmp	3b
+9:	xorl	%eax, %eax
+	movl	%eax, 16(%esp)
+	jmp	4b
+.previous
+	_ASM_EXTABLE(1b, 6b)
+	_ASM_EXTABLE(2b, 7b)
+	_ASM_EXTABLE(3b, 8b)
+	_ASM_EXTABLE(4b, 9b)
+ENDPROC(xen_failsafe_callback)
+
+BUILD_INTERRUPT3(xen_hvm_callback_vector, HYPERVISOR_CALLBACK_VECTOR,
+		xen_evtchn_do_upcall)
+
+#endif /* CONFIG_XEN */
+
+#if IS_ENABLED(CONFIG_HYPERV)
+
+BUILD_INTERRUPT3(hyperv_callback_vector, HYPERVISOR_CALLBACK_VECTOR,
+	hyperv_vector_handler)
+
+#endif /* CONFIG_HYPERV */
+
+#ifdef CONFIG_FUNCTION_TRACER
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+ENTRY(mcount)
+	ret
+END(mcount)
+
+ENTRY(ftrace_caller)
+	pushl	%eax
+	pushl	%ecx
+	pushl	%edx
+	pushl	$0				/* Pass NULL as regs pointer */
+	movl	4*4(%esp), %eax
+	movl	0x4(%ebp), %edx
+	movl	function_trace_op, %ecx
+	subl	$MCOUNT_INSN_SIZE, %eax
+
+.globl ftrace_call
+ftrace_call:
+	call	ftrace_stub
+
+	addl	$4, %esp			/* skip NULL pointer */
+	popl	%edx
+	popl	%ecx
+	popl	%eax
+ftrace_ret:
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+.globl ftrace_graph_call
+ftrace_graph_call:
+	jmp	ftrace_stub
+#endif
+
+.globl ftrace_stub
+ftrace_stub:
+	ret
+END(ftrace_caller)
+
+ENTRY(ftrace_regs_caller)
+	pushf	/* push flags before compare (in cs location) */
+
+	/*
+	 * i386 does not save SS and ESP when coming from kernel.
+	 * Instead, to get sp, &regs->sp is used (see ptrace.h).
+	 * Unfortunately, that means eflags must be at the same location
+	 * as the current return ip is. We move the return ip into the
+	 * ip location, and move flags into the return ip location.
+	 */
+	pushl	4(%esp)				/* save return ip into ip slot */
+
+	pushl	$0				/* Load 0 into orig_ax */
+	pushl	%gs
+	pushl	%fs
+	pushl	%es
+	pushl	%ds
+	pushl	%eax
+	pushl	%ebp
+	pushl	%edi
+	pushl	%esi
+	pushl	%edx
+	pushl	%ecx
+	pushl	%ebx
+
+	movl	13*4(%esp), %eax		/* Get the saved flags */
+	movl	%eax, 14*4(%esp)		/* Move saved flags into regs->flags location */
+						/* clobbering return ip */
+	movl	$__KERNEL_CS, 13*4(%esp)
+
+	movl	12*4(%esp), %eax		/* Load ip (1st parameter) */
+	subl	$MCOUNT_INSN_SIZE, %eax		/* Adjust ip */
+	movl	0x4(%ebp), %edx			/* Load parent ip (2nd parameter) */
+	movl	function_trace_op, %ecx		/* Save ftrace_pos in 3rd parameter */
+	pushl	%esp				/* Save pt_regs as 4th parameter */
+
+GLOBAL(ftrace_regs_call)
+	call	ftrace_stub
+
+	addl	$4, %esp			/* Skip pt_regs */
+	movl	14*4(%esp), %eax		/* Move flags back into cs */
+	movl	%eax, 13*4(%esp)		/* Needed to keep addl	from modifying flags */
+	movl	12*4(%esp), %eax		/* Get return ip from regs->ip */
+	movl	%eax, 14*4(%esp)		/* Put return ip back for ret */
+
+	popl	%ebx
+	popl	%ecx
+	popl	%edx
+	popl	%esi
+	popl	%edi
+	popl	%ebp
+	popl	%eax
+	popl	%ds
+	popl	%es
+	popl	%fs
+	popl	%gs
+	addl	$8, %esp			/* Skip orig_ax and ip */
+	popf					/* Pop flags at end (no addl to corrupt flags) */
+	jmp	ftrace_ret
+
+	popf
+	jmp	ftrace_stub
+#else /* ! CONFIG_DYNAMIC_FTRACE */
+
+ENTRY(mcount)
+	cmpl	$__PAGE_OFFSET, %esp
+	jb	ftrace_stub			/* Paging not enabled yet? */
+
+	cmpl	$ftrace_stub, ftrace_trace_function
+	jnz	trace
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+	cmpl	$ftrace_stub, ftrace_graph_return
+	jnz	ftrace_graph_caller
+
+	cmpl	$ftrace_graph_entry_stub, ftrace_graph_entry
+	jnz	ftrace_graph_caller
+#endif
+.globl ftrace_stub
+ftrace_stub:
+	ret
+
+	/* taken from glibc */
+trace:
+	pushl	%eax
+	pushl	%ecx
+	pushl	%edx
+	movl	0xc(%esp), %eax
+	movl	0x4(%ebp), %edx
+	subl	$MCOUNT_INSN_SIZE, %eax
+
+	call	*ftrace_trace_function
+
+	popl	%edx
+	popl	%ecx
+	popl	%eax
+	jmp	ftrace_stub
+END(mcount)
+#endif /* CONFIG_DYNAMIC_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ENTRY(ftrace_graph_caller)
+	pushl	%eax
+	pushl	%ecx
+	pushl	%edx
+	movl	0xc(%esp), %eax
+	lea	0x4(%ebp), %edx
+	movl	(%ebp), %ecx
+	subl	$MCOUNT_INSN_SIZE, %eax
+	call	prepare_ftrace_return
+	popl	%edx
+	popl	%ecx
+	popl	%eax
+	ret
+END(ftrace_graph_caller)
+
+.globl return_to_handler
+return_to_handler:
+	pushl	%eax
+	pushl	%edx
+	movl	%ebp, %eax
+	call	ftrace_return_to_handler
+	movl	%eax, %ecx
+	popl	%edx
+	popl	%eax
+	jmp	*%ecx
+#endif
+
+#ifdef CONFIG_TRACING
+ENTRY(trace_page_fault)
+	ASM_CLAC
+	pushl	$trace_do_page_fault
+	jmp	error_code
+END(trace_page_fault)
+#endif
+
+ENTRY(page_fault)
+	ASM_CLAC
+	pushl	$do_page_fault
+	ALIGN
+error_code:
+	/* the function address is in %gs's slot on the stack */
+	pushl	%fs
+	pushl	%es
+	pushl	%ds
+	pushl	%eax
+	pushl	%ebp
+	pushl	%edi
+	pushl	%esi
+	pushl	%edx
+	pushl	%ecx
+	pushl	%ebx
+	cld
+	movl	$(__KERNEL_PERCPU), %ecx
+	movl	%ecx, %fs
+	UNWIND_ESPFIX_STACK
+	GS_TO_REG %ecx
+	movl	PT_GS(%esp), %edi		# get the function address
+	movl	PT_ORIG_EAX(%esp), %edx		# get the error code
+	movl	$-1, PT_ORIG_EAX(%esp)		# no syscall to restart
+	REG_TO_PTGS %ecx
+	SET_KERNEL_GS %ecx
+	movl	$(__USER_DS), %ecx
+	movl	%ecx, %ds
+	movl	%ecx, %es
+	TRACE_IRQS_OFF
+	movl	%esp, %eax			# pt_regs pointer
+	call	*%edi
+	jmp	ret_from_exception
+END(page_fault)
+
+/*
+ * Debug traps and NMI can happen at the one SYSENTER instruction
+ * that sets up the real kernel stack. Check here, since we can't
+ * allow the wrong stack to be used.
+ *
+ * "TSS_sysenter_sp0+12" is because the NMI/debug handler will have
+ * already pushed 3 words if it hits on the sysenter instruction:
+ * eflags, cs and eip.
+ *
+ * We just load the right stack, and push the three (known) values
+ * by hand onto the new stack - while updating the return eip past
+ * the instruction that would have done it for sysenter.
+ */
+.macro FIX_STACK offset ok label
+	cmpw	$__KERNEL_CS, 4(%esp)
+	jne	\ok
+\label:
+	movl	TSS_sysenter_sp0 + \offset(%esp), %esp
+	pushfl
+	pushl	$__KERNEL_CS
+	pushl	$sysenter_past_esp
+.endm
+
+ENTRY(debug)
+	ASM_CLAC
+	cmpl	$entry_SYSENTER_32, (%esp)
+	jne	debug_stack_correct
+	FIX_STACK 12, debug_stack_correct, debug_esp_fix_insn
+debug_stack_correct:
+	pushl	$-1				# mark this as an int
+	SAVE_ALL
+	TRACE_IRQS_OFF
+	xorl	%edx, %edx			# error code 0
+	movl	%esp, %eax			# pt_regs pointer
+	call	do_debug
+	jmp	ret_from_exception
+END(debug)
+
+/*
+ * NMI is doubly nasty. It can happen _while_ we're handling
+ * a debug fault, and the debug fault hasn't yet been able to
+ * clear up the stack. So we first check whether we got  an
+ * NMI on the sysenter entry path, but after that we need to
+ * check whether we got an NMI on the debug path where the debug
+ * fault happened on the sysenter path.
+ */
+ENTRY(nmi)
+	ASM_CLAC
+#ifdef CONFIG_X86_ESPFIX32
+	pushl	%eax
+	movl	%ss, %eax
+	cmpw	$__ESPFIX_SS, %ax
+	popl	%eax
+	je	nmi_espfix_stack
+#endif
+	cmpl	$entry_SYSENTER_32, (%esp)
+	je	nmi_stack_fixup
+	pushl	%eax
+	movl	%esp, %eax
+	/*
+	 * Do not access memory above the end of our stack page,
+	 * it might not exist.
+	 */
+	andl	$(THREAD_SIZE-1), %eax
+	cmpl	$(THREAD_SIZE-20), %eax
+	popl	%eax
+	jae	nmi_stack_correct
+	cmpl	$entry_SYSENTER_32, 12(%esp)
+	je	nmi_debug_stack_check
+nmi_stack_correct:
+	pushl	%eax
+	SAVE_ALL
+	xorl	%edx, %edx			# zero error code
+	movl	%esp, %eax			# pt_regs pointer
+	call	do_nmi
+	jmp	restore_all_notrace
+
+nmi_stack_fixup:
+	FIX_STACK 12, nmi_stack_correct, 1
+	jmp	nmi_stack_correct
+
+nmi_debug_stack_check:
+	cmpw	$__KERNEL_CS, 16(%esp)
+	jne	nmi_stack_correct
+	cmpl	$debug, (%esp)
+	jb	nmi_stack_correct
+	cmpl	$debug_esp_fix_insn, (%esp)
+	ja	nmi_stack_correct
+	FIX_STACK 24, nmi_stack_correct, 1
+	jmp	nmi_stack_correct
+
+#ifdef CONFIG_X86_ESPFIX32
+nmi_espfix_stack:
+	/*
+	 * create the pointer to lss back
+	 */
+	pushl	%ss
+	pushl	%esp
+	addl	$4, (%esp)
+	/* copy the iret frame of 12 bytes */
+	.rept 3
+	pushl	16(%esp)
+	.endr
+	pushl	%eax
+	SAVE_ALL
+	FIXUP_ESPFIX_STACK			# %eax == %esp
+	xorl	%edx, %edx			# zero error code
+	call	do_nmi
+	RESTORE_REGS
+	lss	12+4(%esp), %esp		# back to espfix stack
+	jmp	irq_return
+#endif
+END(nmi)
+
+ENTRY(int3)
+	ASM_CLAC
+	pushl	$-1				# mark this as an int
+	SAVE_ALL
+	TRACE_IRQS_OFF
+	xorl	%edx, %edx			# zero error code
+	movl	%esp, %eax			# pt_regs pointer
+	call	do_int3
+	jmp	ret_from_exception
+END(int3)
+
+ENTRY(general_protection)
+	pushl	$do_general_protection
+	jmp	error_code
+END(general_protection)
+
+#ifdef CONFIG_KVM_GUEST
+ENTRY(async_page_fault)
+	ASM_CLAC
+	pushl	$do_async_page_fault
+	jmp	error_code
+END(async_page_fault)
+#endif
diff --git a/kernel/arch/x86/entry/entry_64.S b/kernel/arch/x86/entry/entry_64.S
new file mode 100644
index 000000000..316081a2c
--- /dev/null
+++ b/kernel/arch/x86/entry/entry_64.S
@@ -0,0 +1,1510 @@
+/*
+ *  linux/arch/x86_64/entry.S
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *  Copyright (C) 2000, 2001, 2002  Andi Kleen SuSE Labs
+ *  Copyright (C) 2000  Pavel Machek <pavel@suse.cz>
+ *
+ * entry.S contains the system-call and fault low-level handling routines.
+ *
+ * Some of this is documented in Documentation/x86/entry_64.txt
+ *
+ * A note on terminology:
+ * - iret frame:	Architecture defined interrupt frame from SS to RIP
+ *			at the top of the kernel process stack.
+ *
+ * Some macro usage:
+ * - ENTRY/END:		Define functions in the symbol table.
+ * - TRACE_IRQ_*:	Trace hardirq state for lock debugging.
+ * - idtentry:		Define exception entry points.
+ */
+#include <linux/linkage.h>
+#include <asm/segment.h>
+#include <asm/cache.h>
+#include <asm/errno.h>
+#include "calling.h"
+#include <asm/asm-offsets.h>
+#include <asm/msr.h>
+#include <asm/unistd.h>
+#include <asm/thread_info.h>
+#include <asm/hw_irq.h>
+#include <asm/page_types.h>
+#include <asm/irqflags.h>
+#include <asm/paravirt.h>
+#include <asm/percpu.h>
+#include <asm/asm.h>
+#include <asm/smap.h>
+#include <asm/pgtable_types.h>
+#include <linux/err.h>
+
+/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this.  */
+#include <linux/elf-em.h>
+#define AUDIT_ARCH_X86_64			(EM_X86_64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE)
+#define __AUDIT_ARCH_64BIT			0x80000000
+#define __AUDIT_ARCH_LE				0x40000000
+
+.code64
+.section .entry.text, "ax"
+
+#ifdef CONFIG_PARAVIRT
+ENTRY(native_usergs_sysret64)
+	swapgs
+	sysretq
+ENDPROC(native_usergs_sysret64)
+#endif /* CONFIG_PARAVIRT */
+
+.macro TRACE_IRQS_IRETQ
+#ifdef CONFIG_TRACE_IRQFLAGS
+	bt	$9, EFLAGS(%rsp)		/* interrupts off? */
+	jnc	1f
+	TRACE_IRQS_ON
+1:
+#endif
+.endm
+
+/*
+ * When dynamic function tracer is enabled it will add a breakpoint
+ * to all locations that it is about to modify, sync CPUs, update
+ * all the code, sync CPUs, then remove the breakpoints. In this time
+ * if lockdep is enabled, it might jump back into the debug handler
+ * outside the updating of the IST protection. (TRACE_IRQS_ON/OFF).
+ *
+ * We need to change the IDT table before calling TRACE_IRQS_ON/OFF to
+ * make sure the stack pointer does not get reset back to the top
+ * of the debug stack, and instead just reuses the current stack.
+ */
+#if defined(CONFIG_DYNAMIC_FTRACE) && defined(CONFIG_TRACE_IRQFLAGS)
+
+.macro TRACE_IRQS_OFF_DEBUG
+	call	debug_stack_set_zero
+	TRACE_IRQS_OFF
+	call	debug_stack_reset
+.endm
+
+.macro TRACE_IRQS_ON_DEBUG
+	call	debug_stack_set_zero
+	TRACE_IRQS_ON
+	call	debug_stack_reset
+.endm
+
+.macro TRACE_IRQS_IRETQ_DEBUG
+	bt	$9, EFLAGS(%rsp)		/* interrupts off? */
+	jnc	1f
+	TRACE_IRQS_ON_DEBUG
+1:
+.endm
+
+#else
+# define TRACE_IRQS_OFF_DEBUG			TRACE_IRQS_OFF
+# define TRACE_IRQS_ON_DEBUG			TRACE_IRQS_ON
+# define TRACE_IRQS_IRETQ_DEBUG			TRACE_IRQS_IRETQ
+#endif
+
+/*
+ * 64-bit SYSCALL instruction entry. Up to 6 arguments in registers.
+ *
+ * 64-bit SYSCALL saves rip to rcx, clears rflags.RF, then saves rflags to r11,
+ * then loads new ss, cs, and rip from previously programmed MSRs.
+ * rflags gets masked by a value from another MSR (so CLD and CLAC
+ * are not needed). SYSCALL does not save anything on the stack
+ * and does not change rsp.
+ *
+ * Registers on entry:
+ * rax  system call number
+ * rcx  return address
+ * r11  saved rflags (note: r11 is callee-clobbered register in C ABI)
+ * rdi  arg0
+ * rsi  arg1
+ * rdx  arg2
+ * r10  arg3 (needs to be moved to rcx to conform to C ABI)
+ * r8   arg4
+ * r9   arg5
+ * (note: r12-r15, rbp, rbx are callee-preserved in C ABI)
+ *
+ * Only called from user space.
+ *
+ * When user can change pt_regs->foo always force IRET. That is because
+ * it deals with uncanonical addresses better. SYSRET has trouble
+ * with them due to bugs in both AMD and Intel CPUs.
+ */
+
+ENTRY(entry_SYSCALL_64)
+	/*
+	 * Interrupts are off on entry.
+	 * We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON,
+	 * it is too small to ever cause noticeable irq latency.
+	 */
+	SWAPGS_UNSAFE_STACK
+	/*
+	 * A hypervisor implementation might want to use a label
+	 * after the swapgs, so that it can do the swapgs
+	 * for the guest and jump here on syscall.
+	 */
+GLOBAL(entry_SYSCALL_64_after_swapgs)
+
+	movq	%rsp, PER_CPU_VAR(rsp_scratch)
+	movq	PER_CPU_VAR(cpu_current_top_of_stack), %rsp
+
+	/* Construct struct pt_regs on stack */
+	pushq	$__USER_DS			/* pt_regs->ss */
+	pushq	PER_CPU_VAR(rsp_scratch)	/* pt_regs->sp */
+	/*
+	 * Re-enable interrupts.
+	 * We use 'rsp_scratch' as a scratch space, hence irq-off block above
+	 * must execute atomically in the face of possible interrupt-driven
+	 * task preemption. We must enable interrupts only after we're done
+	 * with using rsp_scratch:
+	 */
+	ENABLE_INTERRUPTS(CLBR_NONE)
+	pushq	%r11				/* pt_regs->flags */
+	pushq	$__USER_CS			/* pt_regs->cs */
+	pushq	%rcx				/* pt_regs->ip */
+	pushq	%rax				/* pt_regs->orig_ax */
+	pushq	%rdi				/* pt_regs->di */
+	pushq	%rsi				/* pt_regs->si */
+	pushq	%rdx				/* pt_regs->dx */
+	pushq	%rcx				/* pt_regs->cx */
+	pushq	$-ENOSYS			/* pt_regs->ax */
+	pushq	%r8				/* pt_regs->r8 */
+	pushq	%r9				/* pt_regs->r9 */
+	pushq	%r10				/* pt_regs->r10 */
+	pushq	%r11				/* pt_regs->r11 */
+	sub	$(6*8), %rsp			/* pt_regs->bp, bx, r12-15 not saved */
+
+	testl	$_TIF_WORK_SYSCALL_ENTRY, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
+	jnz	tracesys
+entry_SYSCALL_64_fastpath:
+#if __SYSCALL_MASK == ~0
+	cmpq	$__NR_syscall_max, %rax
+#else
+	andl	$__SYSCALL_MASK, %eax
+	cmpl	$__NR_syscall_max, %eax
+#endif
+	ja	1f				/* return -ENOSYS (already in pt_regs->ax) */
+	movq	%r10, %rcx
+	call	*sys_call_table(, %rax, 8)
+	movq	%rax, RAX(%rsp)
+1:
+/*
+ * Syscall return path ending with SYSRET (fast path).
+ * Has incompletely filled pt_regs.
+ */
+	LOCKDEP_SYS_EXIT
+	/*
+	 * We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON,
+	 * it is too small to ever cause noticeable irq latency.
+	 */
+	DISABLE_INTERRUPTS(CLBR_NONE)
+
+	/*
+	 * We must check ti flags with interrupts (or at least preemption)
+	 * off because we must *never* return to userspace without
+	 * processing exit work that is enqueued if we're preempted here.
+	 * In particular, returning to userspace with any of the one-shot
+	 * flags (TIF_NOTIFY_RESUME, TIF_USER_RETURN_NOTIFY, etc) set is
+	 * very bad.
+	 */
+	testl	$_TIF_ALLWORK_MASK, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
+	jnz	int_ret_from_sys_call_irqs_off	/* Go to the slow path */
+
+	RESTORE_C_REGS_EXCEPT_RCX_R11
+	movq	RIP(%rsp), %rcx
+	movq	EFLAGS(%rsp), %r11
+	movq	RSP(%rsp), %rsp
+	/*
+	 * 64-bit SYSRET restores rip from rcx,
+	 * rflags from r11 (but RF and VM bits are forced to 0),
+	 * cs and ss are loaded from MSRs.
+	 * Restoration of rflags re-enables interrupts.
+	 *
+	 * NB: On AMD CPUs with the X86_BUG_SYSRET_SS_ATTRS bug, the ss
+	 * descriptor is not reinitialized.  This means that we should
+	 * avoid SYSRET with SS == NULL, which could happen if we schedule,
+	 * exit the kernel, and re-enter using an interrupt vector.  (All
+	 * interrupt entries on x86_64 set SS to NULL.)  We prevent that
+	 * from happening by reloading SS in __switch_to.  (Actually
+	 * detecting the failure in 64-bit userspace is tricky but can be
+	 * done.)
+	 */
+	USERGS_SYSRET64
+
+GLOBAL(int_ret_from_sys_call_irqs_off)
+	TRACE_IRQS_ON
+	ENABLE_INTERRUPTS(CLBR_NONE)
+	jmp int_ret_from_sys_call
+
+	/* Do syscall entry tracing */
+tracesys:
+	movq	%rsp, %rdi
+	movl	$AUDIT_ARCH_X86_64, %esi
+	call	syscall_trace_enter_phase1
+	test	%rax, %rax
+	jnz	tracesys_phase2			/* if needed, run the slow path */
+	RESTORE_C_REGS_EXCEPT_RAX		/* else restore clobbered regs */
+	movq	ORIG_RAX(%rsp), %rax
+	jmp	entry_SYSCALL_64_fastpath	/* and return to the fast path */
+
+tracesys_phase2:
+	SAVE_EXTRA_REGS
+	movq	%rsp, %rdi
+	movl	$AUDIT_ARCH_X86_64, %esi
+	movq	%rax, %rdx
+	call	syscall_trace_enter_phase2
+
+	/*
+	 * Reload registers from stack in case ptrace changed them.
+	 * We don't reload %rax because syscall_trace_entry_phase2() returned
+	 * the value it wants us to use in the table lookup.
+	 */
+	RESTORE_C_REGS_EXCEPT_RAX
+	RESTORE_EXTRA_REGS
+#if __SYSCALL_MASK == ~0
+	cmpq	$__NR_syscall_max, %rax
+#else
+	andl	$__SYSCALL_MASK, %eax
+	cmpl	$__NR_syscall_max, %eax
+#endif
+	ja	1f				/* return -ENOSYS (already in pt_regs->ax) */
+	movq	%r10, %rcx			/* fixup for C */
+	call	*sys_call_table(, %rax, 8)
+	movq	%rax, RAX(%rsp)
+1:
+	/* Use IRET because user could have changed pt_regs->foo */
+
+/*
+ * Syscall return path ending with IRET.
+ * Has correct iret frame.
+ */
+GLOBAL(int_ret_from_sys_call)
+	SAVE_EXTRA_REGS
+	movq	%rsp, %rdi
+	call	syscall_return_slowpath	/* returns with IRQs disabled */
+	RESTORE_EXTRA_REGS
+	TRACE_IRQS_IRETQ		/* we're about to change IF */
+
+	/*
+	 * Try to use SYSRET instead of IRET if we're returning to
+	 * a completely clean 64-bit userspace context.
+	 */
+	movq	RCX(%rsp), %rcx
+	movq	RIP(%rsp), %r11
+	cmpq	%rcx, %r11			/* RCX == RIP */
+	jne	opportunistic_sysret_failed
+
+	/*
+	 * On Intel CPUs, SYSRET with non-canonical RCX/RIP will #GP
+	 * in kernel space.  This essentially lets the user take over
+	 * the kernel, since userspace controls RSP.
+	 *
+	 * If width of "canonical tail" ever becomes variable, this will need
+	 * to be updated to remain correct on both old and new CPUs.
+	 */
+	.ifne __VIRTUAL_MASK_SHIFT - 47
+	.error "virtual address width changed -- SYSRET checks need update"
+	.endif
+
+	/* Change top 16 bits to be the sign-extension of 47th bit */
+	shl	$(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx
+	sar	$(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx
+
+	/* If this changed %rcx, it was not canonical */
+	cmpq	%rcx, %r11
+	jne	opportunistic_sysret_failed
+
+	cmpq	$__USER_CS, CS(%rsp)		/* CS must match SYSRET */
+	jne	opportunistic_sysret_failed
+
+	movq	R11(%rsp), %r11
+	cmpq	%r11, EFLAGS(%rsp)		/* R11 == RFLAGS */
+	jne	opportunistic_sysret_failed
+
+	/*
+	 * SYSRET can't restore RF.  SYSRET can restore TF, but unlike IRET,
+	 * restoring TF results in a trap from userspace immediately after
+	 * SYSRET.  This would cause an infinite loop whenever #DB happens
+	 * with register state that satisfies the opportunistic SYSRET
+	 * conditions.  For example, single-stepping this user code:
+	 *
+	 *           movq	$stuck_here, %rcx
+	 *           pushfq
+	 *           popq %r11
+	 *   stuck_here:
+	 *
+	 * would never get past 'stuck_here'.
+	 */
+	testq	$(X86_EFLAGS_RF|X86_EFLAGS_TF), %r11
+	jnz	opportunistic_sysret_failed
+
+	/* nothing to check for RSP */
+
+	cmpq	$__USER_DS, SS(%rsp)		/* SS must match SYSRET */
+	jne	opportunistic_sysret_failed
+
+	/*
+	 * We win! This label is here just for ease of understanding
+	 * perf profiles. Nothing jumps here.
+	 */
+syscall_return_via_sysret:
+	/* rcx and r11 are already restored (see code above) */
+	RESTORE_C_REGS_EXCEPT_RCX_R11
+	movq	RSP(%rsp), %rsp
+	USERGS_SYSRET64
+
+opportunistic_sysret_failed:
+	SWAPGS
+	jmp	restore_c_regs_and_iret
+END(entry_SYSCALL_64)
+
+
+	.macro FORK_LIKE func
+ENTRY(stub_\func)
+	SAVE_EXTRA_REGS 8
+	jmp	sys_\func
+END(stub_\func)
+	.endm
+
+	FORK_LIKE  clone
+	FORK_LIKE  fork
+	FORK_LIKE  vfork
+
+ENTRY(stub_execve)
+	call	sys_execve
+return_from_execve:
+	testl	%eax, %eax
+	jz	1f
+	/* exec failed, can use fast SYSRET code path in this case */
+	ret
+1:
+	/* must use IRET code path (pt_regs->cs may have changed) */
+	addq	$8, %rsp
+	ZERO_EXTRA_REGS
+	movq	%rax, RAX(%rsp)
+	jmp	int_ret_from_sys_call
+END(stub_execve)
+/*
+ * Remaining execve stubs are only 7 bytes long.
+ * ENTRY() often aligns to 16 bytes, which in this case has no benefits.
+ */
+	.align	8
+GLOBAL(stub_execveat)
+	call	sys_execveat
+	jmp	return_from_execve
+END(stub_execveat)
+
+#if defined(CONFIG_X86_X32_ABI)
+	.align	8
+GLOBAL(stub_x32_execve)
+	call	compat_sys_execve
+	jmp	return_from_execve
+END(stub_x32_execve)
+	.align	8
+GLOBAL(stub_x32_execveat)
+	call	compat_sys_execveat
+	jmp	return_from_execve
+END(stub_x32_execveat)
+#endif
+
+/*
+ * sigreturn is special because it needs to restore all registers on return.
+ * This cannot be done with SYSRET, so use the IRET return path instead.
+ */
+ENTRY(stub_rt_sigreturn)
+	/*
+	 * SAVE_EXTRA_REGS result is not normally needed:
+	 * sigreturn overwrites all pt_regs->GPREGS.
+	 * But sigreturn can fail (!), and there is no easy way to detect that.
+	 * To make sure RESTORE_EXTRA_REGS doesn't restore garbage on error,
+	 * we SAVE_EXTRA_REGS here.
+	 */
+	SAVE_EXTRA_REGS 8
+	call	sys_rt_sigreturn
+return_from_stub:
+	addq	$8, %rsp
+	RESTORE_EXTRA_REGS
+	movq	%rax, RAX(%rsp)
+	jmp	int_ret_from_sys_call
+END(stub_rt_sigreturn)
+
+#ifdef CONFIG_X86_X32_ABI
+ENTRY(stub_x32_rt_sigreturn)
+	SAVE_EXTRA_REGS 8
+	call	sys32_x32_rt_sigreturn
+	jmp	return_from_stub
+END(stub_x32_rt_sigreturn)
+#endif
+
+/*
+ * A newly forked process directly context switches into this address.
+ *
+ * rdi: prev task we switched from
+ */
+ENTRY(ret_from_fork)
+
+	LOCK ; btr $TIF_FORK, TI_flags(%r8)
+
+	pushq	$0x0002
+	popfq					/* reset kernel eflags */
+
+	call	schedule_tail			/* rdi: 'prev' task parameter */
+
+	RESTORE_EXTRA_REGS
+
+	testb	$3, CS(%rsp)			/* from kernel_thread? */
+
+	/*
+	 * By the time we get here, we have no idea whether our pt_regs,
+	 * ti flags, and ti status came from the 64-bit SYSCALL fast path,
+	 * the slow path, or one of the 32-bit compat paths.
+	 * Use IRET code path to return, since it can safely handle
+	 * all of the above.
+	 */
+	jnz	int_ret_from_sys_call
+
+	/*
+	 * We came from kernel_thread
+	 * nb: we depend on RESTORE_EXTRA_REGS above
+	 */
+	movq	%rbp, %rdi
+	call	*%rbx
+	movl	$0, RAX(%rsp)
+	RESTORE_EXTRA_REGS
+	jmp	int_ret_from_sys_call
+END(ret_from_fork)
+
+/*
+ * Build the entry stubs with some assembler magic.
+ * We pack 1 stub into every 8-byte block.
+ */
+	.align 8
+ENTRY(irq_entries_start)
+    vector=FIRST_EXTERNAL_VECTOR
+    .rept (FIRST_SYSTEM_VECTOR - FIRST_EXTERNAL_VECTOR)
+	pushq	$(~vector+0x80)			/* Note: always in signed byte range */
+    vector=vector+1
+	jmp	common_interrupt
+	.align	8
+    .endr
+END(irq_entries_start)
+
+/*
+ * Interrupt entry/exit.
+ *
+ * Interrupt entry points save only callee clobbered registers in fast path.
+ *
+ * Entry runs with interrupts off.
+ */
+
+/* 0(%rsp): ~(interrupt number) */
+	.macro interrupt func
+	cld
+	ALLOC_PT_GPREGS_ON_STACK
+	SAVE_C_REGS
+	SAVE_EXTRA_REGS
+
+	testb	$3, CS(%rsp)
+	jz	1f
+
+	/*
+	 * IRQ from user mode.  Switch to kernel gsbase and inform context
+	 * tracking that we're in kernel mode.
+	 */
+	SWAPGS
+
+	/*
+	 * We need to tell lockdep that IRQs are off.  We can't do this until
+	 * we fix gsbase, and we should do it before enter_from_user_mode
+	 * (which can take locks).  Since TRACE_IRQS_OFF idempotent,
+	 * the simplest way to handle it is to just call it twice if
+	 * we enter from user mode.  There's no reason to optimize this since
+	 * TRACE_IRQS_OFF is a no-op if lockdep is off.
+	 */
+	TRACE_IRQS_OFF
+
+#ifdef CONFIG_CONTEXT_TRACKING
+	call enter_from_user_mode
+#endif
+
+1:
+	/*
+	 * Save previous stack pointer, optionally switch to interrupt stack.
+	 * irq_count is used to check if a CPU is already on an interrupt stack
+	 * or not. While this is essentially redundant with preempt_count it is
+	 * a little cheaper to use a separate counter in the PDA (short of
+	 * moving irq_enter into assembly, which would be too much work)
+	 */
+	movq	%rsp, %rdi
+	incl	PER_CPU_VAR(irq_count)
+	cmovzq	PER_CPU_VAR(irq_stack_ptr), %rsp
+	pushq	%rdi
+	/* We entered an interrupt context - irqs are off: */
+	TRACE_IRQS_OFF
+
+	call	\func	/* rdi points to pt_regs */
+	.endm
+
+	/*
+	 * The interrupt stubs push (~vector+0x80) onto the stack and
+	 * then jump to common_interrupt.
+	 */
+	.p2align CONFIG_X86_L1_CACHE_SHIFT
+common_interrupt:
+	ASM_CLAC
+	addq	$-0x80, (%rsp)			/* Adjust vector to [-256, -1] range */
+	interrupt do_IRQ
+	/* 0(%rsp): old RSP */
+ret_from_intr:
+	DISABLE_INTERRUPTS(CLBR_NONE)
+	TRACE_IRQS_OFF
+	decl	PER_CPU_VAR(irq_count)
+
+	/* Restore saved previous stack */
+	popq	%rsp
+
+	testb	$3, CS(%rsp)
+	jz	retint_kernel
+
+	/* Interrupt came from user space */
+GLOBAL(retint_user)
+	mov	%rsp,%rdi
+	call	prepare_exit_to_usermode
+	TRACE_IRQS_IRETQ
+	SWAPGS
+	jmp	restore_regs_and_iret
+
+/* Returning to kernel space */
+retint_kernel:
+#ifdef CONFIG_PREEMPT
+	/* Interrupts are off */
+	/* Check if we need preemption */
+	bt	$9, EFLAGS(%rsp)		/* were interrupts off? */
+	jnc	1f
+0:	cmpl	$0, PER_CPU_VAR(__preempt_count)
+#ifndef CONFIG_PREEMPT_LAZY
+	jnz	1f
+#else
+	jz	do_preempt_schedule_irq
+
+	# atleast preempt count == 0 ?
+	cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count)
+	jnz	1f
+
+	GET_THREAD_INFO(%rcx)
+	cmpl	$0, TI_preempt_lazy_count(%rcx)
+	jnz	1f
+
+	bt	$TIF_NEED_RESCHED_LAZY,TI_flags(%rcx)
+	jnc	1f
+do_preempt_schedule_irq:
+#endif
+	call	preempt_schedule_irq
+	jmp	0b
+1:
+#endif
+	/*
+	 * The iretq could re-enable interrupts:
+	 */
+	TRACE_IRQS_IRETQ
+
+/*
+ * At this label, code paths which return to kernel and to user,
+ * which come from interrupts/exception and from syscalls, merge.
+ */
+GLOBAL(restore_regs_and_iret)
+	RESTORE_EXTRA_REGS
+restore_c_regs_and_iret:
+	RESTORE_C_REGS
+	REMOVE_PT_GPREGS_FROM_STACK 8
+	INTERRUPT_RETURN
+
+ENTRY(native_iret)
+	/*
+	 * Are we returning to a stack segment from the LDT?  Note: in
+	 * 64-bit mode SS:RSP on the exception stack is always valid.
+	 */
+#ifdef CONFIG_X86_ESPFIX64
+	testb	$4, (SS-RIP)(%rsp)
+	jnz	native_irq_return_ldt
+#endif
+
+.global native_irq_return_iret
+native_irq_return_iret:
+	/*
+	 * This may fault.  Non-paranoid faults on return to userspace are
+	 * handled by fixup_bad_iret.  These include #SS, #GP, and #NP.
+	 * Double-faults due to espfix64 are handled in do_double_fault.
+	 * Other faults here are fatal.
+	 */
+	iretq
+
+#ifdef CONFIG_X86_ESPFIX64
+native_irq_return_ldt:
+	pushq	%rax
+	pushq	%rdi
+	SWAPGS
+	movq	PER_CPU_VAR(espfix_waddr), %rdi
+	movq	%rax, (0*8)(%rdi)		/* RAX */
+	movq	(2*8)(%rsp), %rax		/* RIP */
+	movq	%rax, (1*8)(%rdi)
+	movq	(3*8)(%rsp), %rax		/* CS */
+	movq	%rax, (2*8)(%rdi)
+	movq	(4*8)(%rsp), %rax		/* RFLAGS */
+	movq	%rax, (3*8)(%rdi)
+	movq	(6*8)(%rsp), %rax		/* SS */
+	movq	%rax, (5*8)(%rdi)
+	movq	(5*8)(%rsp), %rax		/* RSP */
+	movq	%rax, (4*8)(%rdi)
+	andl	$0xffff0000, %eax
+	popq	%rdi
+	orq	PER_CPU_VAR(espfix_stack), %rax
+	SWAPGS
+	movq	%rax, %rsp
+	popq	%rax
+	jmp	native_irq_return_iret
+#endif
+END(common_interrupt)
+
+/*
+ * APIC interrupts.
+ */
+.macro apicinterrupt3 num sym do_sym
+ENTRY(\sym)
+	ASM_CLAC
+	pushq	$~(\num)
+.Lcommon_\sym:
+	interrupt \do_sym
+	jmp	ret_from_intr
+END(\sym)
+.endm
+
+#ifdef CONFIG_TRACING
+#define trace(sym) trace_##sym
+#define smp_trace(sym) smp_trace_##sym
+
+.macro trace_apicinterrupt num sym
+apicinterrupt3 \num trace(\sym) smp_trace(\sym)
+.endm
+#else
+.macro trace_apicinterrupt num sym do_sym
+.endm
+#endif
+
+.macro apicinterrupt num sym do_sym
+apicinterrupt3 \num \sym \do_sym
+trace_apicinterrupt \num \sym
+.endm
+
+#ifdef CONFIG_SMP
+apicinterrupt3 IRQ_MOVE_CLEANUP_VECTOR		irq_move_cleanup_interrupt	smp_irq_move_cleanup_interrupt
+apicinterrupt3 REBOOT_VECTOR			reboot_interrupt		smp_reboot_interrupt
+#endif
+
+#ifdef CONFIG_X86_UV
+apicinterrupt3 UV_BAU_MESSAGE			uv_bau_message_intr1		uv_bau_message_interrupt
+#endif
+
+apicinterrupt LOCAL_TIMER_VECTOR		apic_timer_interrupt		smp_apic_timer_interrupt
+apicinterrupt X86_PLATFORM_IPI_VECTOR		x86_platform_ipi		smp_x86_platform_ipi
+
+#ifdef CONFIG_HAVE_KVM
+apicinterrupt3 POSTED_INTR_VECTOR		kvm_posted_intr_ipi		smp_kvm_posted_intr_ipi
+apicinterrupt3 POSTED_INTR_WAKEUP_VECTOR	kvm_posted_intr_wakeup_ipi	smp_kvm_posted_intr_wakeup_ipi
+#endif
+
+#ifdef CONFIG_X86_MCE_THRESHOLD
+apicinterrupt THRESHOLD_APIC_VECTOR		threshold_interrupt		smp_threshold_interrupt
+#endif
+
+#ifdef CONFIG_X86_MCE_AMD
+apicinterrupt DEFERRED_ERROR_VECTOR		deferred_error_interrupt	smp_deferred_error_interrupt
+#endif
+
+#ifdef CONFIG_X86_THERMAL_VECTOR
+apicinterrupt THERMAL_APIC_VECTOR		thermal_interrupt		smp_thermal_interrupt
+#endif
+
+#ifdef CONFIG_SMP
+apicinterrupt CALL_FUNCTION_SINGLE_VECTOR	call_function_single_interrupt	smp_call_function_single_interrupt
+apicinterrupt CALL_FUNCTION_VECTOR		call_function_interrupt		smp_call_function_interrupt
+apicinterrupt RESCHEDULE_VECTOR			reschedule_interrupt		smp_reschedule_interrupt
+#endif
+
+apicinterrupt ERROR_APIC_VECTOR			error_interrupt			smp_error_interrupt
+apicinterrupt SPURIOUS_APIC_VECTOR		spurious_interrupt		smp_spurious_interrupt
+
+#ifdef CONFIG_IRQ_WORK
+apicinterrupt IRQ_WORK_VECTOR			irq_work_interrupt		smp_irq_work_interrupt
+#endif
+
+/*
+ * Exception entry points.
+ */
+#define CPU_TSS_IST(x) PER_CPU_VAR(cpu_tss) + (TSS_ist + ((x) - 1) * 8)
+
+.macro idtentry sym do_sym has_error_code:req paranoid=0 shift_ist=-1
+ENTRY(\sym)
+	/* Sanity check */
+	.if \shift_ist != -1 && \paranoid == 0
+	.error "using shift_ist requires paranoid=1"
+	.endif
+
+	ASM_CLAC
+	PARAVIRT_ADJUST_EXCEPTION_FRAME
+
+	.ifeq \has_error_code
+	pushq	$-1				/* ORIG_RAX: no syscall to restart */
+	.endif
+
+	ALLOC_PT_GPREGS_ON_STACK
+
+	.if \paranoid
+	.if \paranoid == 1
+	testb	$3, CS(%rsp)			/* If coming from userspace, switch stacks */
+	jnz	1f
+	.endif
+	call	paranoid_entry
+	.else
+	call	error_entry
+	.endif
+	/* returned flag: ebx=0: need swapgs on exit, ebx=1: don't need it */
+
+	.if \paranoid
+	.if \shift_ist != -1
+	TRACE_IRQS_OFF_DEBUG			/* reload IDT in case of recursion */
+	.else
+	TRACE_IRQS_OFF
+	.endif
+	.endif
+
+	movq	%rsp, %rdi			/* pt_regs pointer */
+
+	.if \has_error_code
+	movq	ORIG_RAX(%rsp), %rsi		/* get error code */
+	movq	$-1, ORIG_RAX(%rsp)		/* no syscall to restart */
+	.else
+	xorl	%esi, %esi			/* no error code */
+	.endif
+
+	.if \shift_ist != -1
+	subq	$EXCEPTION_STKSZ, CPU_TSS_IST(\shift_ist)
+	.endif
+
+	call	\do_sym
+
+	.if \shift_ist != -1
+	addq	$EXCEPTION_STKSZ, CPU_TSS_IST(\shift_ist)
+	.endif
+
+	/* these procedures expect "no swapgs" flag in ebx */
+	.if \paranoid
+	jmp	paranoid_exit
+	.else
+	jmp	error_exit
+	.endif
+
+	.if \paranoid == 1
+	/*
+	 * Paranoid entry from userspace.  Switch stacks and treat it
+	 * as a normal entry.  This means that paranoid handlers
+	 * run in real process context if user_mode(regs).
+	 */
+1:
+	call	error_entry
+
+
+	movq	%rsp, %rdi			/* pt_regs pointer */
+	call	sync_regs
+	movq	%rax, %rsp			/* switch stack */
+
+	movq	%rsp, %rdi			/* pt_regs pointer */
+
+	.if \has_error_code
+	movq	ORIG_RAX(%rsp), %rsi		/* get error code */
+	movq	$-1, ORIG_RAX(%rsp)		/* no syscall to restart */
+	.else
+	xorl	%esi, %esi			/* no error code */
+	.endif
+
+	call	\do_sym
+
+	jmp	error_exit			/* %ebx: no swapgs flag */
+	.endif
+END(\sym)
+.endm
+
+#ifdef CONFIG_TRACING
+.macro trace_idtentry sym do_sym has_error_code:req
+idtentry trace(\sym) trace(\do_sym) has_error_code=\has_error_code
+idtentry \sym \do_sym has_error_code=\has_error_code
+.endm
+#else
+.macro trace_idtentry sym do_sym has_error_code:req
+idtentry \sym \do_sym has_error_code=\has_error_code
+.endm
+#endif
+
+idtentry divide_error			do_divide_error			has_error_code=0
+idtentry overflow			do_overflow			has_error_code=0
+idtentry bounds				do_bounds			has_error_code=0
+idtentry invalid_op			do_invalid_op			has_error_code=0
+idtentry device_not_available		do_device_not_available		has_error_code=0
+idtentry double_fault			do_double_fault			has_error_code=1 paranoid=2
+idtentry coprocessor_segment_overrun	do_coprocessor_segment_overrun	has_error_code=0
+idtentry invalid_TSS			do_invalid_TSS			has_error_code=1
+idtentry segment_not_present		do_segment_not_present		has_error_code=1
+idtentry spurious_interrupt_bug		do_spurious_interrupt_bug	has_error_code=0
+idtentry coprocessor_error		do_coprocessor_error		has_error_code=0
+idtentry alignment_check		do_alignment_check		has_error_code=1
+idtentry simd_coprocessor_error		do_simd_coprocessor_error	has_error_code=0
+
+
+	/*
+	 * Reload gs selector with exception handling
+	 * edi:  new selector
+	 */
+ENTRY(native_load_gs_index)
+	pushfq
+	DISABLE_INTERRUPTS(CLBR_ANY & ~CLBR_RDI)
+	SWAPGS
+gs_change:
+	movl	%edi, %gs
+2:	mfence					/* workaround */
+	SWAPGS
+	popfq
+	ret
+END(native_load_gs_index)
+
+	_ASM_EXTABLE(gs_change, bad_gs)
+	.section .fixup, "ax"
+	/* running with kernelgs */
+bad_gs:
+	SWAPGS					/* switch back to user gs */
+	xorl	%eax, %eax
+	movl	%eax, %gs
+	jmp	2b
+	.previous
+
+#ifndef CONFIG_PREEMPT_RT_FULL
+/* Call softirq on interrupt stack. Interrupts are off. */
+ENTRY(do_softirq_own_stack)
+	pushq	%rbp
+	mov	%rsp, %rbp
+	incl	PER_CPU_VAR(irq_count)
+	cmove	PER_CPU_VAR(irq_stack_ptr), %rsp
+	push	%rbp				/* frame pointer backlink */
+	call	__do_softirq
+	leaveq
+	decl	PER_CPU_VAR(irq_count)
+	ret
+END(do_softirq_own_stack)
+#endif
+
+#ifdef CONFIG_XEN
+idtentry xen_hypervisor_callback xen_do_hypervisor_callback has_error_code=0
+
+/*
+ * A note on the "critical region" in our callback handler.
+ * We want to avoid stacking callback handlers due to events occurring
+ * during handling of the last event. To do this, we keep events disabled
+ * until we've done all processing. HOWEVER, we must enable events before
+ * popping the stack frame (can't be done atomically) and so it would still
+ * be possible to get enough handler activations to overflow the stack.
+ * Although unlikely, bugs of that kind are hard to track down, so we'd
+ * like to avoid the possibility.
+ * So, on entry to the handler we detect whether we interrupted an
+ * existing activation in its critical region -- if so, we pop the current
+ * activation and restart the handler using the previous one.
+ */
+ENTRY(xen_do_hypervisor_callback)		/* do_hypervisor_callback(struct *pt_regs) */
+
+/*
+ * Since we don't modify %rdi, evtchn_do_upall(struct *pt_regs) will
+ * see the correct pointer to the pt_regs
+ */
+	movq	%rdi, %rsp			/* we don't return, adjust the stack frame */
+11:	incl	PER_CPU_VAR(irq_count)
+	movq	%rsp, %rbp
+	cmovzq	PER_CPU_VAR(irq_stack_ptr), %rsp
+	pushq	%rbp				/* frame pointer backlink */
+	call	xen_evtchn_do_upcall
+	popq	%rsp
+	decl	PER_CPU_VAR(irq_count)
+#ifndef CONFIG_PREEMPT
+	call	xen_maybe_preempt_hcall
+#endif
+	jmp	error_exit
+END(xen_do_hypervisor_callback)
+
+/*
+ * Hypervisor uses this for application faults while it executes.
+ * We get here for two reasons:
+ *  1. Fault while reloading DS, ES, FS or GS
+ *  2. Fault while executing IRET
+ * Category 1 we do not need to fix up as Xen has already reloaded all segment
+ * registers that could be reloaded and zeroed the others.
+ * Category 2 we fix up by killing the current process. We cannot use the
+ * normal Linux return path in this case because if we use the IRET hypercall
+ * to pop the stack frame we end up in an infinite loop of failsafe callbacks.
+ * We distinguish between categories by comparing each saved segment register
+ * with its current contents: any discrepancy means we in category 1.
+ */
+ENTRY(xen_failsafe_callback)
+	movl	%ds, %ecx
+	cmpw	%cx, 0x10(%rsp)
+	jne	1f
+	movl	%es, %ecx
+	cmpw	%cx, 0x18(%rsp)
+	jne	1f
+	movl	%fs, %ecx
+	cmpw	%cx, 0x20(%rsp)
+	jne	1f
+	movl	%gs, %ecx
+	cmpw	%cx, 0x28(%rsp)
+	jne	1f
+	/* All segments match their saved values => Category 2 (Bad IRET). */
+	movq	(%rsp), %rcx
+	movq	8(%rsp), %r11
+	addq	$0x30, %rsp
+	pushq	$0				/* RIP */
+	pushq	%r11
+	pushq	%rcx
+	jmp	general_protection
+1:	/* Segment mismatch => Category 1 (Bad segment). Retry the IRET. */
+	movq	(%rsp), %rcx
+	movq	8(%rsp), %r11
+	addq	$0x30, %rsp
+	pushq	$-1 /* orig_ax = -1 => not a system call */
+	ALLOC_PT_GPREGS_ON_STACK
+	SAVE_C_REGS
+	SAVE_EXTRA_REGS
+	jmp	error_exit
+END(xen_failsafe_callback)
+
+apicinterrupt3 HYPERVISOR_CALLBACK_VECTOR \
+	xen_hvm_callback_vector xen_evtchn_do_upcall
+
+#endif /* CONFIG_XEN */
+
+#if IS_ENABLED(CONFIG_HYPERV)
+apicinterrupt3 HYPERVISOR_CALLBACK_VECTOR \
+	hyperv_callback_vector hyperv_vector_handler
+#endif /* CONFIG_HYPERV */
+
+idtentry debug			do_debug		has_error_code=0	paranoid=1 shift_ist=DEBUG_STACK
+idtentry int3			do_int3			has_error_code=0	paranoid=1 shift_ist=DEBUG_STACK
+idtentry stack_segment		do_stack_segment	has_error_code=1
+
+#ifdef CONFIG_XEN
+idtentry xen_debug		do_debug		has_error_code=0
+idtentry xen_int3		do_int3			has_error_code=0
+idtentry xen_stack_segment	do_stack_segment	has_error_code=1
+#endif
+
+idtentry general_protection	do_general_protection	has_error_code=1
+trace_idtentry page_fault	do_page_fault		has_error_code=1
+
+#ifdef CONFIG_KVM_GUEST
+idtentry async_page_fault	do_async_page_fault	has_error_code=1
+#endif
+
+#ifdef CONFIG_X86_MCE
+idtentry machine_check					has_error_code=0	paranoid=1 do_sym=*machine_check_vector(%rip)
+#endif
+
+/*
+ * Save all registers in pt_regs, and switch gs if needed.
+ * Use slow, but surefire "are we in kernel?" check.
+ * Return: ebx=0: need swapgs on exit, ebx=1: otherwise
+ */
+ENTRY(paranoid_entry)
+	cld
+	SAVE_C_REGS 8
+	SAVE_EXTRA_REGS 8
+	movl	$1, %ebx
+	movl	$MSR_GS_BASE, %ecx
+	rdmsr
+	testl	%edx, %edx
+	js	1f				/* negative -> in kernel */
+	SWAPGS
+	xorl	%ebx, %ebx
+1:	ret
+END(paranoid_entry)
+
+/*
+ * "Paranoid" exit path from exception stack.  This is invoked
+ * only on return from non-NMI IST interrupts that came
+ * from kernel space.
+ *
+ * We may be returning to very strange contexts (e.g. very early
+ * in syscall entry), so checking for preemption here would
+ * be complicated.  Fortunately, we there's no good reason
+ * to try to handle preemption here.
+ *
+ * On entry, ebx is "no swapgs" flag (1: don't need swapgs, 0: need it)
+ */
+ENTRY(paranoid_exit)
+	DISABLE_INTERRUPTS(CLBR_NONE)
+	TRACE_IRQS_OFF_DEBUG
+	testl	%ebx, %ebx			/* swapgs needed? */
+	jnz	paranoid_exit_no_swapgs
+	TRACE_IRQS_IRETQ
+	SWAPGS_UNSAFE_STACK
+	jmp	paranoid_exit_restore
+paranoid_exit_no_swapgs:
+	TRACE_IRQS_IRETQ_DEBUG
+paranoid_exit_restore:
+	RESTORE_EXTRA_REGS
+	RESTORE_C_REGS
+	REMOVE_PT_GPREGS_FROM_STACK 8
+	INTERRUPT_RETURN
+END(paranoid_exit)
+
+/*
+ * Save all registers in pt_regs, and switch gs if needed.
+ * Return: EBX=0: came from user mode; EBX=1: otherwise
+ */
+ENTRY(error_entry)
+	cld
+	SAVE_C_REGS 8
+	SAVE_EXTRA_REGS 8
+	xorl	%ebx, %ebx
+	testb	$3, CS+8(%rsp)
+	jz	.Lerror_kernelspace
+
+.Lerror_entry_from_usermode_swapgs:
+	/*
+	 * We entered from user mode or we're pretending to have entered
+	 * from user mode due to an IRET fault.
+	 */
+	SWAPGS
+
+.Lerror_entry_from_usermode_after_swapgs:
+	/*
+	 * We need to tell lockdep that IRQs are off.  We can't do this until
+	 * we fix gsbase, and we should do it before enter_from_user_mode
+	 * (which can take locks).
+	 */
+	TRACE_IRQS_OFF
+#ifdef CONFIG_CONTEXT_TRACKING
+	call enter_from_user_mode
+#endif
+	ret
+
+.Lerror_entry_done:
+	TRACE_IRQS_OFF
+	ret
+
+	/*
+	 * There are two places in the kernel that can potentially fault with
+	 * usergs. Handle them here.  B stepping K8s sometimes report a
+	 * truncated RIP for IRET exceptions returning to compat mode. Check
+	 * for these here too.
+	 */
+.Lerror_kernelspace:
+	incl	%ebx
+	leaq	native_irq_return_iret(%rip), %rcx
+	cmpq	%rcx, RIP+8(%rsp)
+	je	.Lerror_bad_iret
+	movl	%ecx, %eax			/* zero extend */
+	cmpq	%rax, RIP+8(%rsp)
+	je	.Lbstep_iret
+	cmpq	$gs_change, RIP+8(%rsp)
+	jne	.Lerror_entry_done
+
+	/*
+	 * hack: gs_change can fail with user gsbase.  If this happens, fix up
+	 * gsbase and proceed.  We'll fix up the exception and land in
+	 * gs_change's error handler with kernel gsbase.
+	 */
+	jmp	.Lerror_entry_from_usermode_swapgs
+
+.Lbstep_iret:
+	/* Fix truncated RIP */
+	movq	%rcx, RIP+8(%rsp)
+	/* fall through */
+
+.Lerror_bad_iret:
+	/*
+	 * We came from an IRET to user mode, so we have user gsbase.
+	 * Switch to kernel gsbase:
+	 */
+	SWAPGS
+
+	/*
+	 * Pretend that the exception came from user mode: set up pt_regs
+	 * as if we faulted immediately after IRET and clear EBX so that
+	 * error_exit knows that we will be returning to user mode.
+	 */
+	mov	%rsp, %rdi
+	call	fixup_bad_iret
+	mov	%rax, %rsp
+	decl	%ebx
+	jmp	.Lerror_entry_from_usermode_after_swapgs
+END(error_entry)
+
+
+/*
+ * On entry, EBS is a "return to kernel mode" flag:
+ *   1: already in kernel mode, don't need SWAPGS
+ *   0: user gsbase is loaded, we need SWAPGS and standard preparation for return to usermode
+ */
+ENTRY(error_exit)
+	movl	%ebx, %eax
+	DISABLE_INTERRUPTS(CLBR_NONE)
+	TRACE_IRQS_OFF
+	testl	%eax, %eax
+	jnz	retint_kernel
+	jmp	retint_user
+END(error_exit)
+
+/* Runs on exception stack */
+ENTRY(nmi)
+	/*
+	 * Fix up the exception frame if we're on Xen.
+	 * PARAVIRT_ADJUST_EXCEPTION_FRAME is guaranteed to push at most
+	 * one value to the stack on native, so it may clobber the rdx
+	 * scratch slot, but it won't clobber any of the important
+	 * slots past it.
+	 *
+	 * Xen is a different story, because the Xen frame itself overlaps
+	 * the "NMI executing" variable.
+	 */
+	PARAVIRT_ADJUST_EXCEPTION_FRAME
+
+	/*
+	 * We allow breakpoints in NMIs. If a breakpoint occurs, then
+	 * the iretq it performs will take us out of NMI context.
+	 * This means that we can have nested NMIs where the next
+	 * NMI is using the top of the stack of the previous NMI. We
+	 * can't let it execute because the nested NMI will corrupt the
+	 * stack of the previous NMI. NMI handlers are not re-entrant
+	 * anyway.
+	 *
+	 * To handle this case we do the following:
+	 *  Check the a special location on the stack that contains
+	 *  a variable that is set when NMIs are executing.
+	 *  The interrupted task's stack is also checked to see if it
+	 *  is an NMI stack.
+	 *  If the variable is not set and the stack is not the NMI
+	 *  stack then:
+	 *    o Set the special variable on the stack
+	 *    o Copy the interrupt frame into an "outermost" location on the
+	 *      stack
+	 *    o Copy the interrupt frame into an "iret" location on the stack
+	 *    o Continue processing the NMI
+	 *  If the variable is set or the previous stack is the NMI stack:
+	 *    o Modify the "iret" location to jump to the repeat_nmi
+	 *    o return back to the first NMI
+	 *
+	 * Now on exit of the first NMI, we first clear the stack variable
+	 * The NMI stack will tell any nested NMIs at that point that it is
+	 * nested. Then we pop the stack normally with iret, and if there was
+	 * a nested NMI that updated the copy interrupt stack frame, a
+	 * jump will be made to the repeat_nmi code that will handle the second
+	 * NMI.
+	 *
+	 * However, espfix prevents us from directly returning to userspace
+	 * with a single IRET instruction.  Similarly, IRET to user mode
+	 * can fault.  We therefore handle NMIs from user space like
+	 * other IST entries.
+	 */
+
+	/* Use %rdx as our temp variable throughout */
+	pushq	%rdx
+
+	testb	$3, CS-RIP+8(%rsp)
+	jz	.Lnmi_from_kernel
+
+	/*
+	 * NMI from user mode.  We need to run on the thread stack, but we
+	 * can't go through the normal entry paths: NMIs are masked, and
+	 * we don't want to enable interrupts, because then we'll end
+	 * up in an awkward situation in which IRQs are on but NMIs
+	 * are off.
+	 *
+	 * We also must not push anything to the stack before switching
+	 * stacks lest we corrupt the "NMI executing" variable.
+	 */
+
+	SWAPGS_UNSAFE_STACK
+	cld
+	movq	%rsp, %rdx
+	movq	PER_CPU_VAR(cpu_current_top_of_stack), %rsp
+	pushq	5*8(%rdx)	/* pt_regs->ss */
+	pushq	4*8(%rdx)	/* pt_regs->rsp */
+	pushq	3*8(%rdx)	/* pt_regs->flags */
+	pushq	2*8(%rdx)	/* pt_regs->cs */
+	pushq	1*8(%rdx)	/* pt_regs->rip */
+	pushq   $-1		/* pt_regs->orig_ax */
+	pushq   %rdi		/* pt_regs->di */
+	pushq   %rsi		/* pt_regs->si */
+	pushq   (%rdx)		/* pt_regs->dx */
+	pushq   %rcx		/* pt_regs->cx */
+	pushq   %rax		/* pt_regs->ax */
+	pushq   %r8		/* pt_regs->r8 */
+	pushq   %r9		/* pt_regs->r9 */
+	pushq   %r10		/* pt_regs->r10 */
+	pushq   %r11		/* pt_regs->r11 */
+	pushq	%rbx		/* pt_regs->rbx */
+	pushq	%rbp		/* pt_regs->rbp */
+	pushq	%r12		/* pt_regs->r12 */
+	pushq	%r13		/* pt_regs->r13 */
+	pushq	%r14		/* pt_regs->r14 */
+	pushq	%r15		/* pt_regs->r15 */
+
+	/*
+	 * At this point we no longer need to worry about stack damage
+	 * due to nesting -- we're on the normal thread stack and we're
+	 * done with the NMI stack.
+	 */
+
+	movq	%rsp, %rdi
+	movq	$-1, %rsi
+	call	do_nmi
+
+	/*
+	 * Return back to user mode.  We must *not* do the normal exit
+	 * work, because we don't want to enable interrupts.  Fortunately,
+	 * do_nmi doesn't modify pt_regs.
+	 */
+	SWAPGS
+	jmp	restore_c_regs_and_iret
+
+.Lnmi_from_kernel:
+	/*
+	 * Here's what our stack frame will look like:
+	 * +---------------------------------------------------------+
+	 * | original SS                                             |
+	 * | original Return RSP                                     |
+	 * | original RFLAGS                                         |
+	 * | original CS                                             |
+	 * | original RIP                                            |
+	 * +---------------------------------------------------------+
+	 * | temp storage for rdx                                    |
+	 * +---------------------------------------------------------+
+	 * | "NMI executing" variable                                |
+	 * +---------------------------------------------------------+
+	 * | iret SS          } Copied from "outermost" frame        |
+	 * | iret Return RSP  } on each loop iteration; overwritten  |
+	 * | iret RFLAGS      } by a nested NMI to force another     |
+	 * | iret CS          } iteration if needed.                 |
+	 * | iret RIP         }                                      |
+	 * +---------------------------------------------------------+
+	 * | outermost SS          } initialized in first_nmi;       |
+	 * | outermost Return RSP  } will not be changed before      |
+	 * | outermost RFLAGS      } NMI processing is done.         |
+	 * | outermost CS          } Copied to "iret" frame on each  |
+	 * | outermost RIP         } iteration.                      |
+	 * +---------------------------------------------------------+
+	 * | pt_regs                                                 |
+	 * +---------------------------------------------------------+
+	 *
+	 * The "original" frame is used by hardware.  Before re-enabling
+	 * NMIs, we need to be done with it, and we need to leave enough
+	 * space for the asm code here.
+	 *
+	 * We return by executing IRET while RSP points to the "iret" frame.
+	 * That will either return for real or it will loop back into NMI
+	 * processing.
+	 *
+	 * The "outermost" frame is copied to the "iret" frame on each
+	 * iteration of the loop, so each iteration starts with the "iret"
+	 * frame pointing to the final return target.
+	 */
+
+	/*
+	 * Determine whether we're a nested NMI.
+	 *
+	 * If we interrupted kernel code between repeat_nmi and
+	 * end_repeat_nmi, then we are a nested NMI.  We must not
+	 * modify the "iret" frame because it's being written by
+	 * the outer NMI.  That's okay; the outer NMI handler is
+	 * about to about to call do_nmi anyway, so we can just
+	 * resume the outer NMI.
+	 */
+
+	movq	$repeat_nmi, %rdx
+	cmpq	8(%rsp), %rdx
+	ja	1f
+	movq	$end_repeat_nmi, %rdx
+	cmpq	8(%rsp), %rdx
+	ja	nested_nmi_out
+1:
+
+	/*
+	 * Now check "NMI executing".  If it's set, then we're nested.
+	 * This will not detect if we interrupted an outer NMI just
+	 * before IRET.
+	 */
+	cmpl	$1, -8(%rsp)
+	je	nested_nmi
+
+	/*
+	 * Now test if the previous stack was an NMI stack.  This covers
+	 * the case where we interrupt an outer NMI after it clears
+	 * "NMI executing" but before IRET.  We need to be careful, though:
+	 * there is one case in which RSP could point to the NMI stack
+	 * despite there being no NMI active: naughty userspace controls
+	 * RSP at the very beginning of the SYSCALL targets.  We can
+	 * pull a fast one on naughty userspace, though: we program
+	 * SYSCALL to mask DF, so userspace cannot cause DF to be set
+	 * if it controls the kernel's RSP.  We set DF before we clear
+	 * "NMI executing".
+	 */
+	lea	6*8(%rsp), %rdx
+	/* Compare the NMI stack (rdx) with the stack we came from (4*8(%rsp)) */
+	cmpq	%rdx, 4*8(%rsp)
+	/* If the stack pointer is above the NMI stack, this is a normal NMI */
+	ja	first_nmi
+
+	subq	$EXCEPTION_STKSZ, %rdx
+	cmpq	%rdx, 4*8(%rsp)
+	/* If it is below the NMI stack, it is a normal NMI */
+	jb	first_nmi
+
+	/* Ah, it is within the NMI stack. */
+
+	testb	$(X86_EFLAGS_DF >> 8), (3*8 + 1)(%rsp)
+	jz	first_nmi	/* RSP was user controlled. */
+
+	/* This is a nested NMI. */
+
+nested_nmi:
+	/*
+	 * Modify the "iret" frame to point to repeat_nmi, forcing another
+	 * iteration of NMI handling.
+	 */
+	subq	$8, %rsp
+	leaq	-10*8(%rsp), %rdx
+	pushq	$__KERNEL_DS
+	pushq	%rdx
+	pushfq
+	pushq	$__KERNEL_CS
+	pushq	$repeat_nmi
+
+	/* Put stack back */
+	addq	$(6*8), %rsp
+
+nested_nmi_out:
+	popq	%rdx
+
+	/* We are returning to kernel mode, so this cannot result in a fault. */
+	INTERRUPT_RETURN
+
+first_nmi:
+	/* Restore rdx. */
+	movq	(%rsp), %rdx
+
+	/* Make room for "NMI executing". */
+	pushq	$0
+
+	/* Leave room for the "iret" frame */
+	subq	$(5*8), %rsp
+
+	/* Copy the "original" frame to the "outermost" frame */
+	.rept 5
+	pushq	11*8(%rsp)
+	.endr
+
+	/* Everything up to here is safe from nested NMIs */
+
+#ifdef CONFIG_DEBUG_ENTRY
+	/*
+	 * For ease of testing, unmask NMIs right away.  Disabled by
+	 * default because IRET is very expensive.
+	 */
+	pushq	$0		/* SS */
+	pushq	%rsp		/* RSP (minus 8 because of the previous push) */
+	addq	$8, (%rsp)	/* Fix up RSP */
+	pushfq			/* RFLAGS */
+	pushq	$__KERNEL_CS	/* CS */
+	pushq	$1f		/* RIP */
+	INTERRUPT_RETURN	/* continues at repeat_nmi below */
+1:
+#endif
+
+repeat_nmi:
+	/*
+	 * If there was a nested NMI, the first NMI's iret will return
+	 * here. But NMIs are still enabled and we can take another
+	 * nested NMI. The nested NMI checks the interrupted RIP to see
+	 * if it is between repeat_nmi and end_repeat_nmi, and if so
+	 * it will just return, as we are about to repeat an NMI anyway.
+	 * This makes it safe to copy to the stack frame that a nested
+	 * NMI will update.
+	 *
+	 * RSP is pointing to "outermost RIP".  gsbase is unknown, but, if
+	 * we're repeating an NMI, gsbase has the same value that it had on
+	 * the first iteration.  paranoid_entry will load the kernel
+	 * gsbase if needed before we call do_nmi.  "NMI executing"
+	 * is zero.
+	 */
+	movq	$1, 10*8(%rsp)		/* Set "NMI executing". */
+
+	/*
+	 * Copy the "outermost" frame to the "iret" frame.  NMIs that nest
+	 * here must not modify the "iret" frame while we're writing to
+	 * it or it will end up containing garbage.
+	 */
+	addq	$(10*8), %rsp
+	.rept 5
+	pushq	-6*8(%rsp)
+	.endr
+	subq	$(5*8), %rsp
+end_repeat_nmi:
+
+	/*
+	 * Everything below this point can be preempted by a nested NMI.
+	 * If this happens, then the inner NMI will change the "iret"
+	 * frame to point back to repeat_nmi.
+	 */
+	pushq	$-1				/* ORIG_RAX: no syscall to restart */
+	ALLOC_PT_GPREGS_ON_STACK
+
+	/*
+	 * Use paranoid_entry to handle SWAPGS, but no need to use paranoid_exit
+	 * as we should not be calling schedule in NMI context.
+	 * Even with normal interrupts enabled. An NMI should not be
+	 * setting NEED_RESCHED or anything that normal interrupts and
+	 * exceptions might do.
+	 */
+	call	paranoid_entry
+
+	/* paranoidentry do_nmi, 0; without TRACE_IRQS_OFF */
+	movq	%rsp, %rdi
+	movq	$-1, %rsi
+	call	do_nmi
+
+	testl	%ebx, %ebx			/* swapgs needed? */
+	jnz	nmi_restore
+nmi_swapgs:
+	SWAPGS_UNSAFE_STACK
+nmi_restore:
+	RESTORE_EXTRA_REGS
+	RESTORE_C_REGS
+
+	/* Point RSP at the "iret" frame. */
+	REMOVE_PT_GPREGS_FROM_STACK 6*8
+
+	/*
+	 * Clear "NMI executing".  Set DF first so that we can easily
+	 * distinguish the remaining code between here and IRET from
+	 * the SYSCALL entry and exit paths.  On a native kernel, we
+	 * could just inspect RIP, but, on paravirt kernels,
+	 * INTERRUPT_RETURN can translate into a jump into a
+	 * hypercall page.
+	 */
+	std
+	movq	$0, 5*8(%rsp)		/* clear "NMI executing" */
+
+	/*
+	 * INTERRUPT_RETURN reads the "iret" frame and exits the NMI
+	 * stack in a single instruction.  We are returning to kernel
+	 * mode, so this cannot result in a fault.
+	 */
+	INTERRUPT_RETURN
+END(nmi)
+
+ENTRY(ignore_sysret)
+	mov	$-ENOSYS, %eax
+	sysret
+END(ignore_sysret)
diff --git a/kernel/arch/x86/entry/entry_64_compat.S b/kernel/arch/x86/entry/entry_64_compat.S
new file mode 100644
index 000000000..15cfebaa7
--- /dev/null
+++ b/kernel/arch/x86/entry/entry_64_compat.S
@@ -0,0 +1,328 @@
+/*
+ * Compatibility mode system call entry point for x86-64.
+ *
+ * Copyright 2000-2002 Andi Kleen, SuSE Labs.
+ */
+#include "calling.h"
+#include <asm/asm-offsets.h>
+#include <asm/current.h>
+#include <asm/errno.h>
+#include <asm/ia32_unistd.h>
+#include <asm/thread_info.h>
+#include <asm/segment.h>
+#include <asm/irqflags.h>
+#include <asm/asm.h>
+#include <asm/smap.h>
+#include <linux/linkage.h>
+#include <linux/err.h>
+
+	.section .entry.text, "ax"
+
+#ifdef CONFIG_PARAVIRT
+ENTRY(native_usergs_sysret32)
+	swapgs
+	sysretl
+ENDPROC(native_usergs_sysret32)
+#endif
+
+/*
+ * 32-bit SYSENTER instruction entry.
+ *
+ * SYSENTER loads ss, rsp, cs, and rip from previously programmed MSRs.
+ * IF and VM in rflags are cleared (IOW: interrupts are off).
+ * SYSENTER does not save anything on the stack,
+ * and does not save old rip (!!!) and rflags.
+ *
+ * Arguments:
+ * eax  system call number
+ * ebx  arg1
+ * ecx  arg2
+ * edx  arg3
+ * esi  arg4
+ * edi  arg5
+ * ebp  user stack
+ * 0(%ebp) arg6
+ *
+ * This is purely a fast path. For anything complicated we use the int 0x80
+ * path below. We set up a complete hardware stack frame to share code
+ * with the int 0x80 path.
+ */
+ENTRY(entry_SYSENTER_compat)
+	/* Interrupts are off on entry. */
+	SWAPGS_UNSAFE_STACK
+	movq	PER_CPU_VAR(cpu_current_top_of_stack), %rsp
+
+	/*
+	 * User tracing code (ptrace or signal handlers) might assume that
+	 * the saved RAX contains a 32-bit number when we're invoking a 32-bit
+	 * syscall.  Just in case the high bits are nonzero, zero-extend
+	 * the syscall number.  (This could almost certainly be deleted
+	 * with no ill effects.)
+	 */
+	movl	%eax, %eax
+
+	/* Construct struct pt_regs on stack */
+	pushq	$__USER32_DS		/* pt_regs->ss */
+	pushq	%rbp			/* pt_regs->sp (stashed in bp) */
+
+	/*
+	 * Push flags.  This is nasty.  First, interrupts are currently
+	 * off, but we need pt_regs->flags to have IF set.  Second, even
+	 * if TF was set when SYSENTER started, it's clear by now.  We fix
+	 * that later using TIF_SINGLESTEP.
+	 */
+	pushfq				/* pt_regs->flags (except IF = 0) */
+	orl	$X86_EFLAGS_IF, (%rsp)	/* Fix saved flags */
+	ASM_CLAC			/* Clear AC after saving FLAGS */
+
+	pushq	$__USER32_CS		/* pt_regs->cs */
+	xorq    %r8,%r8
+	pushq	%r8			/* pt_regs->ip = 0 (placeholder) */
+	pushq	%rax			/* pt_regs->orig_ax */
+	pushq	%rdi			/* pt_regs->di */
+	pushq	%rsi			/* pt_regs->si */
+	pushq	%rdx			/* pt_regs->dx */
+	pushq	%rcx			/* pt_regs->cx */
+	pushq	$-ENOSYS		/* pt_regs->ax */
+	pushq   %r8                     /* pt_regs->r8  = 0 */
+	pushq   %r8                     /* pt_regs->r9  = 0 */
+	pushq   %r8                     /* pt_regs->r10 = 0 */
+	pushq   %r8                     /* pt_regs->r11 = 0 */
+	pushq   %rbx                    /* pt_regs->rbx */
+	pushq   %rbp                    /* pt_regs->rbp (will be overwritten) */
+	pushq   %r8                     /* pt_regs->r12 = 0 */
+	pushq   %r8                     /* pt_regs->r13 = 0 */
+	pushq   %r8                     /* pt_regs->r14 = 0 */
+	pushq   %r8                     /* pt_regs->r15 = 0 */
+	cld
+
+	/*
+	 * Sysenter doesn't filter flags, so we need to clear NT
+	 * ourselves.  To save a few cycles, we can check whether
+	 * NT was set instead of doing an unconditional popfq.
+	 * This needs to happen before enabling interrupts so that
+	 * we don't get preempted with NT set.
+	 *
+	 * NB.: sysenter_fix_flags is a label with the code under it moved
+	 * out-of-line as an optimization: NT is unlikely to be set in the
+	 * majority of the cases and instead of polluting the I$ unnecessarily,
+	 * we're keeping that code behind a branch which will predict as
+	 * not-taken and therefore its instructions won't be fetched.
+	 */
+	testl	$X86_EFLAGS_NT, EFLAGS(%rsp)
+	jnz	sysenter_fix_flags
+sysenter_flags_fixed:
+
+	/*
+	 * User mode is traced as though IRQs are on, and SYSENTER
+	 * turned them off.
+	 */
+	TRACE_IRQS_OFF
+
+	movq	%rsp, %rdi
+	call	do_fast_syscall_32
+	/* XEN PV guests always use IRET path */
+	ALTERNATIVE "testl %eax, %eax; jz .Lsyscall_32_done", \
+		    "jmp .Lsyscall_32_done", X86_FEATURE_XENPV
+	jmp	sysret32_from_system_call
+
+sysenter_fix_flags:
+	pushq	$X86_EFLAGS_FIXED
+	popfq
+	jmp	sysenter_flags_fixed
+ENDPROC(entry_SYSENTER_compat)
+
+/*
+ * 32-bit SYSCALL instruction entry.
+ *
+ * 32-bit SYSCALL saves rip to rcx, clears rflags.RF, then saves rflags to r11,
+ * then loads new ss, cs, and rip from previously programmed MSRs.
+ * rflags gets masked by a value from another MSR (so CLD and CLAC
+ * are not needed). SYSCALL does not save anything on the stack
+ * and does not change rsp.
+ *
+ * Note: rflags saving+masking-with-MSR happens only in Long mode
+ * (in legacy 32-bit mode, IF, RF and VM bits are cleared and that's it).
+ * Don't get confused: rflags saving+masking depends on Long Mode Active bit
+ * (EFER.LMA=1), NOT on bitness of userspace where SYSCALL executes
+ * or target CS descriptor's L bit (SYSCALL does not read segment descriptors).
+ *
+ * Arguments:
+ * eax  system call number
+ * ecx  return address
+ * ebx  arg1
+ * ebp  arg2	(note: not saved in the stack frame, should not be touched)
+ * edx  arg3
+ * esi  arg4
+ * edi  arg5
+ * esp  user stack
+ * 0(%esp) arg6
+ */
+ENTRY(entry_SYSCALL_compat)
+	/* Interrupts are off on entry. */
+	SWAPGS_UNSAFE_STACK
+
+	/* Stash user ESP and switch to the kernel stack. */
+	movl	%esp, %r8d
+	movq	PER_CPU_VAR(cpu_current_top_of_stack), %rsp
+
+	/* Zero-extending 32-bit regs, do not remove */
+	movl	%eax, %eax
+
+	/* Construct struct pt_regs on stack */
+	pushq	$__USER32_DS		/* pt_regs->ss */
+	pushq	%r8			/* pt_regs->sp */
+	pushq	%r11			/* pt_regs->flags */
+	pushq	$__USER32_CS		/* pt_regs->cs */
+	pushq	%rcx			/* pt_regs->ip */
+	pushq	%rax			/* pt_regs->orig_ax */
+	pushq	%rdi			/* pt_regs->di */
+	pushq	%rsi			/* pt_regs->si */
+	pushq	%rdx			/* pt_regs->dx */
+	pushq	%rbp			/* pt_regs->cx (stashed in bp) */
+	pushq	$-ENOSYS		/* pt_regs->ax */
+	xorq    %r8,%r8
+	pushq   %r8                     /* pt_regs->r8  = 0 */
+	pushq   %r8                     /* pt_regs->r9  = 0 */
+	pushq   %r8                     /* pt_regs->r10 = 0 */
+	pushq   %r8                     /* pt_regs->r11 = 0 */
+	pushq   %rbx                    /* pt_regs->rbx */
+	pushq   %rbp                    /* pt_regs->rbp (will be overwritten) */
+	pushq   %r8                     /* pt_regs->r12 = 0 */
+	pushq   %r8                     /* pt_regs->r13 = 0 */
+	pushq   %r8                     /* pt_regs->r14 = 0 */
+	pushq   %r8                     /* pt_regs->r15 = 0 */
+
+	/*
+	 * User mode is traced as though IRQs are on, and SYSENTER
+	 * turned them off.
+	 */
+	TRACE_IRQS_OFF
+
+	movq	%rsp, %rdi
+	call	do_fast_syscall_32
+	/* XEN PV guests always use IRET path */
+	ALTERNATIVE "testl %eax, %eax; jz .Lsyscall_32_done", \
+		    "jmp .Lsyscall_32_done", X86_FEATURE_XENPV
+
+	/* Opportunistic SYSRET */
+sysret32_from_system_call:
+	TRACE_IRQS_ON			/* User mode traces as IRQs on. */
+	movq	RBX(%rsp), %rbx		/* pt_regs->rbx */
+	movq	RBP(%rsp), %rbp		/* pt_regs->rbp */
+	movq	EFLAGS(%rsp), %r11	/* pt_regs->flags (in r11) */
+	movq	RIP(%rsp), %rcx		/* pt_regs->ip (in rcx) */
+	addq	$RAX, %rsp		/* Skip r8-r15 */
+	popq	%rax			/* pt_regs->rax */
+	popq	%rdx			/* Skip pt_regs->cx */
+	popq	%rdx			/* pt_regs->dx */
+	popq	%rsi			/* pt_regs->si */
+	popq	%rdi			/* pt_regs->di */
+
+        /*
+         * USERGS_SYSRET32 does:
+         *  GSBASE = user's GS base
+         *  EIP = ECX
+         *  RFLAGS = R11
+         *  CS = __USER32_CS
+         *  SS = __USER_DS
+         *
+	 * ECX will not match pt_regs->cx, but we're returning to a vDSO
+	 * trampoline that will fix up RCX, so this is okay.
+	 *
+	 * R12-R15 are callee-saved, so they contain whatever was in them
+	 * when the system call started, which is already known to user
+	 * code.  We zero R8-R10 to avoid info leaks.
+         */
+	xorq	%r8, %r8
+	xorq	%r9, %r9
+	xorq	%r10, %r10
+	movq	RSP-ORIG_RAX(%rsp), %rsp
+        USERGS_SYSRET32
+END(entry_SYSCALL_compat)
+
+/*
+ * Emulated IA32 system calls via int 0x80.
+ *
+ * Arguments:
+ * eax  system call number
+ * ebx  arg1
+ * ecx  arg2
+ * edx  arg3
+ * esi  arg4
+ * edi  arg5
+ * ebp  arg6	(note: not saved in the stack frame, should not be touched)
+ *
+ * Notes:
+ * Uses the same stack frame as the x86-64 version.
+ * All registers except eax must be saved (but ptrace may violate that).
+ * Arguments are zero extended. For system calls that want sign extension and
+ * take long arguments a wrapper is needed. Most calls can just be called
+ * directly.
+ * Assumes it is only called from user space and entered with interrupts off.
+ */
+
+ENTRY(entry_INT80_compat)
+	/*
+	 * Interrupts are off on entry.
+	 */
+	PARAVIRT_ADJUST_EXCEPTION_FRAME
+	ASM_CLAC			/* Do this early to minimize exposure */
+	SWAPGS
+
+	/*
+	 * User tracing code (ptrace or signal handlers) might assume that
+	 * the saved RAX contains a 32-bit number when we're invoking a 32-bit
+	 * syscall.  Just in case the high bits are nonzero, zero-extend
+	 * the syscall number.  (This could almost certainly be deleted
+	 * with no ill effects.)
+	 */
+	movl	%eax, %eax
+
+	/* Construct struct pt_regs on stack (iret frame is already on stack) */
+	pushq	%rax			/* pt_regs->orig_ax */
+	pushq	%rdi			/* pt_regs->di */
+	pushq	%rsi			/* pt_regs->si */
+	pushq	%rdx			/* pt_regs->dx */
+	pushq	%rcx			/* pt_regs->cx */
+	pushq	$-ENOSYS		/* pt_regs->ax */
+	xorq    %r8,%r8
+	pushq   %r8                     /* pt_regs->r8  = 0 */
+	pushq   %r8                     /* pt_regs->r9  = 0 */
+	pushq   %r8                     /* pt_regs->r10 = 0 */
+	pushq   %r8                     /* pt_regs->r11 = 0 */
+	pushq   %rbx                    /* pt_regs->rbx */
+	pushq   %rbp                    /* pt_regs->rbp */
+	pushq   %r12                    /* pt_regs->r12 */
+	pushq   %r13                    /* pt_regs->r13 */
+	pushq   %r14                    /* pt_regs->r14 */
+	pushq   %r15                    /* pt_regs->r15 */
+	cld
+
+	/*
+	 * User mode is traced as though IRQs are on, and the interrupt
+	 * gate turned them off.
+	 */
+	TRACE_IRQS_OFF
+
+	movq	%rsp, %rdi
+	call	do_syscall_32_irqs_off
+.Lsyscall_32_done:
+
+	/* Go back to user mode. */
+	TRACE_IRQS_ON
+	SWAPGS
+	jmp	restore_regs_and_iret
+END(entry_INT80_compat)
+
+	ALIGN
+GLOBAL(stub32_clone)
+	/*
+	 * The 32-bit clone ABI is: clone(..., int tls_val, int *child_tidptr).
+	 * The 64-bit clone ABI is: clone(..., int *child_tidptr, int tls_val).
+	 *
+	 * The native 64-bit kernel's sys_clone() implements the latter,
+	 * so we need to swap arguments here before calling it:
+	 */
+	xchg	%r8, %rcx
+	jmp	sys_clone
diff --git a/kernel/arch/x86/entry/syscall_32.c b/kernel/arch/x86/entry/syscall_32.c
new file mode 100644
index 000000000..9a6649857
--- /dev/null
+++ b/kernel/arch/x86/entry/syscall_32.c
@@ -0,0 +1,30 @@
+/* System call table for i386. */
+
+#include <linux/linkage.h>
+#include <linux/sys.h>
+#include <linux/cache.h>
+#include <asm/asm-offsets.h>
+#include <asm/syscall.h>
+
+#ifdef CONFIG_IA32_EMULATION
+#define SYM(sym, compat) compat
+#else
+#define SYM(sym, compat) sym
+#endif
+
+#define __SYSCALL_I386(nr, sym, compat) extern asmlinkage long SYM(sym, compat)(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long) ;
+#include <asm/syscalls_32.h>
+#undef __SYSCALL_I386
+
+#define __SYSCALL_I386(nr, sym, compat) [nr] = SYM(sym, compat),
+
+extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
+
+__visible const sys_call_ptr_t ia32_sys_call_table[__NR_syscall_compat_max+1] = {
+	/*
+	 * Smells like a compiler bug -- it doesn't work
+	 * when the & below is removed.
+	 */
+	[0 ... __NR_syscall_compat_max] = &sys_ni_syscall,
+#include <asm/syscalls_32.h>
+};
diff --git a/kernel/arch/x86/entry/syscall_64.c b/kernel/arch/x86/entry/syscall_64.c
new file mode 100644
index 000000000..41283d22b
--- /dev/null
+++ b/kernel/arch/x86/entry/syscall_64.c
@@ -0,0 +1,32 @@
+/* System call table for x86-64. */
+
+#include <linux/linkage.h>
+#include <linux/sys.h>
+#include <linux/cache.h>
+#include <asm/asm-offsets.h>
+#include <asm/syscall.h>
+
+#define __SYSCALL_COMMON(nr, sym, compat) __SYSCALL_64(nr, sym, compat)
+
+#ifdef CONFIG_X86_X32_ABI
+# define __SYSCALL_X32(nr, sym, compat) __SYSCALL_64(nr, sym, compat)
+#else
+# define __SYSCALL_X32(nr, sym, compat) /* nothing */
+#endif
+
+#define __SYSCALL_64(nr, sym, compat) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long) ;
+#include <asm/syscalls_64.h>
+#undef __SYSCALL_64
+
+#define __SYSCALL_64(nr, sym, compat) [nr] = sym,
+
+extern long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
+
+asmlinkage const sys_call_ptr_t sys_call_table[__NR_syscall_max+1] = {
+	/*
+	 * Smells like a compiler bug -- it doesn't work
+	 * when the & below is removed.
+	 */
+	[0 ... __NR_syscall_max] = &sys_ni_syscall,
+#include <asm/syscalls_64.h>
+};
diff --git a/kernel/arch/x86/entry/syscalls/Makefile b/kernel/arch/x86/entry/syscalls/Makefile
new file mode 100644
index 000000000..57aa59fd1
--- /dev/null
+++ b/kernel/arch/x86/entry/syscalls/Makefile
@@ -0,0 +1,69 @@
+out := $(obj)/../../include/generated/asm
+uapi := $(obj)/../../include/generated/uapi/asm
+
+# Create output directory if not already present
+_dummy := $(shell [ -d '$(out)' ] || mkdir -p '$(out)') \
+	  $(shell [ -d '$(uapi)' ] || mkdir -p '$(uapi)')
+
+syscall32 := $(srctree)/$(src)/syscall_32.tbl
+syscall64 := $(srctree)/$(src)/syscall_64.tbl
+
+syshdr := $(srctree)/$(src)/syscallhdr.sh
+systbl := $(srctree)/$(src)/syscalltbl.sh
+
+quiet_cmd_syshdr = SYSHDR  $@
+      cmd_syshdr = $(CONFIG_SHELL) '$(syshdr)' '$<' '$@' \
+		   '$(syshdr_abi_$(basetarget))' \
+		   '$(syshdr_pfx_$(basetarget))' \
+		   '$(syshdr_offset_$(basetarget))'
+quiet_cmd_systbl = SYSTBL  $@
+      cmd_systbl = $(CONFIG_SHELL) '$(systbl)' $< $@
+
+quiet_cmd_hypercalls = HYPERCALLS $@
+      cmd_hypercalls = $(CONFIG_SHELL) '$<' $@ $(filter-out $<,$^)
+
+syshdr_abi_unistd_32 := i386
+$(uapi)/unistd_32.h: $(syscall32) $(syshdr)
+	$(call if_changed,syshdr)
+
+syshdr_abi_unistd_32_ia32 := i386
+syshdr_pfx_unistd_32_ia32 := ia32_
+$(out)/unistd_32_ia32.h: $(syscall32) $(syshdr)
+	$(call if_changed,syshdr)
+
+syshdr_abi_unistd_x32 := common,x32
+syshdr_offset_unistd_x32 := __X32_SYSCALL_BIT
+$(uapi)/unistd_x32.h: $(syscall64) $(syshdr)
+	$(call if_changed,syshdr)
+
+syshdr_abi_unistd_64 := common,64
+$(uapi)/unistd_64.h: $(syscall64) $(syshdr)
+	$(call if_changed,syshdr)
+
+syshdr_abi_unistd_64_x32 := x32
+syshdr_pfx_unistd_64_x32 := x32_
+$(out)/unistd_64_x32.h: $(syscall64) $(syshdr)
+	$(call if_changed,syshdr)
+
+$(out)/syscalls_32.h: $(syscall32) $(systbl)
+	$(call if_changed,systbl)
+$(out)/syscalls_64.h: $(syscall64) $(systbl)
+	$(call if_changed,systbl)
+
+$(out)/xen-hypercalls.h: $(srctree)/scripts/xen-hypercalls.sh
+	$(call if_changed,hypercalls)
+
+$(out)/xen-hypercalls.h: $(srctree)/include/xen/interface/xen*.h
+
+uapisyshdr-y			+= unistd_32.h unistd_64.h unistd_x32.h
+syshdr-y			+= syscalls_32.h
+syshdr-$(CONFIG_X86_64)		+= unistd_32_ia32.h unistd_64_x32.h
+syshdr-$(CONFIG_X86_64)		+= syscalls_64.h
+syshdr-$(CONFIG_XEN)		+= xen-hypercalls.h
+
+targets	+= $(uapisyshdr-y) $(syshdr-y)
+
+PHONY += all
+all: $(addprefix $(uapi)/,$(uapisyshdr-y))
+all: $(addprefix $(out)/,$(syshdr-y))
+	@:
diff --git a/kernel/arch/x86/entry/syscalls/syscall_32.tbl b/kernel/arch/x86/entry/syscalls/syscall_32.tbl
new file mode 100644
index 000000000..f17705e13
--- /dev/null
+++ b/kernel/arch/x86/entry/syscalls/syscall_32.tbl
@@ -0,0 +1,385 @@
+#
+# 32-bit system call numbers and entry vectors
+#
+# The format is:
+# <number> <abi> <name> <entry point> <compat entry point>
+#
+# The abi is always "i386" for this file.
+#
+0	i386	restart_syscall		sys_restart_syscall
+1	i386	exit			sys_exit
+2	i386	fork			sys_fork			sys_fork
+3	i386	read			sys_read
+4	i386	write			sys_write
+5	i386	open			sys_open			compat_sys_open
+6	i386	close			sys_close
+7	i386	waitpid			sys_waitpid			sys32_waitpid
+8	i386	creat			sys_creat
+9	i386	link			sys_link
+10	i386	unlink			sys_unlink
+11	i386	execve			sys_execve			compat_sys_execve
+12	i386	chdir			sys_chdir
+13	i386	time			sys_time			compat_sys_time
+14	i386	mknod			sys_mknod
+15	i386	chmod			sys_chmod
+16	i386	lchown			sys_lchown16
+17	i386	break
+18	i386	oldstat			sys_stat
+19	i386	lseek			sys_lseek			compat_sys_lseek
+20	i386	getpid			sys_getpid
+21	i386	mount			sys_mount			compat_sys_mount
+22	i386	umount			sys_oldumount
+23	i386	setuid			sys_setuid16
+24	i386	getuid			sys_getuid16
+25	i386	stime			sys_stime			compat_sys_stime
+26	i386	ptrace			sys_ptrace			compat_sys_ptrace
+27	i386	alarm			sys_alarm
+28	i386	oldfstat		sys_fstat
+29	i386	pause			sys_pause
+30	i386	utime			sys_utime			compat_sys_utime
+31	i386	stty
+32	i386	gtty
+33	i386	access			sys_access
+34	i386	nice			sys_nice
+35	i386	ftime
+36	i386	sync			sys_sync
+37	i386	kill			sys_kill
+38	i386	rename			sys_rename
+39	i386	mkdir			sys_mkdir
+40	i386	rmdir			sys_rmdir
+41	i386	dup			sys_dup
+42	i386	pipe			sys_pipe
+43	i386	times			sys_times			compat_sys_times
+44	i386	prof
+45	i386	brk			sys_brk
+46	i386	setgid			sys_setgid16
+47	i386	getgid			sys_getgid16
+48	i386	signal			sys_signal
+49	i386	geteuid			sys_geteuid16
+50	i386	getegid			sys_getegid16
+51	i386	acct			sys_acct
+52	i386	umount2			sys_umount
+53	i386	lock
+54	i386	ioctl			sys_ioctl			compat_sys_ioctl
+55	i386	fcntl			sys_fcntl			compat_sys_fcntl64
+56	i386	mpx
+57	i386	setpgid			sys_setpgid
+58	i386	ulimit
+59	i386	oldolduname		sys_olduname
+60	i386	umask			sys_umask
+61	i386	chroot			sys_chroot
+62	i386	ustat			sys_ustat			compat_sys_ustat
+63	i386	dup2			sys_dup2
+64	i386	getppid			sys_getppid
+65	i386	getpgrp			sys_getpgrp
+66	i386	setsid			sys_setsid
+67	i386	sigaction		sys_sigaction			compat_sys_sigaction
+68	i386	sgetmask		sys_sgetmask
+69	i386	ssetmask		sys_ssetmask
+70	i386	setreuid		sys_setreuid16
+71	i386	setregid		sys_setregid16
+72	i386	sigsuspend		sys_sigsuspend			sys_sigsuspend
+73	i386	sigpending		sys_sigpending			compat_sys_sigpending
+74	i386	sethostname		sys_sethostname
+75	i386	setrlimit		sys_setrlimit			compat_sys_setrlimit
+76	i386	getrlimit		sys_old_getrlimit		compat_sys_old_getrlimit
+77	i386	getrusage		sys_getrusage			compat_sys_getrusage
+78	i386	gettimeofday		sys_gettimeofday		compat_sys_gettimeofday
+79	i386	settimeofday		sys_settimeofday		compat_sys_settimeofday
+80	i386	getgroups		sys_getgroups16
+81	i386	setgroups		sys_setgroups16
+82	i386	select			sys_old_select			compat_sys_old_select
+83	i386	symlink			sys_symlink
+84	i386	oldlstat		sys_lstat
+85	i386	readlink		sys_readlink
+86	i386	uselib			sys_uselib
+87	i386	swapon			sys_swapon
+88	i386	reboot			sys_reboot
+89	i386	readdir			sys_old_readdir			compat_sys_old_readdir
+90	i386	mmap			sys_old_mmap			sys32_mmap
+91	i386	munmap			sys_munmap
+92	i386	truncate		sys_truncate			compat_sys_truncate
+93	i386	ftruncate		sys_ftruncate			compat_sys_ftruncate
+94	i386	fchmod			sys_fchmod
+95	i386	fchown			sys_fchown16
+96	i386	getpriority		sys_getpriority
+97	i386	setpriority		sys_setpriority
+98	i386	profil
+99	i386	statfs			sys_statfs			compat_sys_statfs
+100	i386	fstatfs			sys_fstatfs			compat_sys_fstatfs
+101	i386	ioperm			sys_ioperm
+102	i386	socketcall		sys_socketcall			compat_sys_socketcall
+103	i386	syslog			sys_syslog
+104	i386	setitimer		sys_setitimer			compat_sys_setitimer
+105	i386	getitimer		sys_getitimer			compat_sys_getitimer
+106	i386	stat			sys_newstat			compat_sys_newstat
+107	i386	lstat			sys_newlstat			compat_sys_newlstat
+108	i386	fstat			sys_newfstat			compat_sys_newfstat
+109	i386	olduname		sys_uname
+110	i386	iopl			sys_iopl
+111	i386	vhangup			sys_vhangup
+112	i386	idle
+113	i386	vm86old			sys_vm86old			sys_ni_syscall
+114	i386	wait4			sys_wait4			compat_sys_wait4
+115	i386	swapoff			sys_swapoff
+116	i386	sysinfo			sys_sysinfo			compat_sys_sysinfo
+117	i386	ipc			sys_ipc				compat_sys_ipc
+118	i386	fsync			sys_fsync
+119	i386	sigreturn		sys_sigreturn			sys32_sigreturn
+120	i386	clone			sys_clone			stub32_clone
+121	i386	setdomainname		sys_setdomainname
+122	i386	uname			sys_newuname
+123	i386	modify_ldt		sys_modify_ldt
+124	i386	adjtimex		sys_adjtimex			compat_sys_adjtimex
+125	i386	mprotect		sys_mprotect
+126	i386	sigprocmask		sys_sigprocmask			compat_sys_sigprocmask
+127	i386	create_module
+128	i386	init_module		sys_init_module
+129	i386	delete_module		sys_delete_module
+130	i386	get_kernel_syms
+131	i386	quotactl		sys_quotactl			sys32_quotactl
+132	i386	getpgid			sys_getpgid
+133	i386	fchdir			sys_fchdir
+134	i386	bdflush			sys_bdflush
+135	i386	sysfs			sys_sysfs
+136	i386	personality		sys_personality
+137	i386	afs_syscall
+138	i386	setfsuid		sys_setfsuid16
+139	i386	setfsgid		sys_setfsgid16
+140	i386	_llseek			sys_llseek
+141	i386	getdents		sys_getdents			compat_sys_getdents
+142	i386	_newselect		sys_select			compat_sys_select
+143	i386	flock			sys_flock
+144	i386	msync			sys_msync
+145	i386	readv			sys_readv			compat_sys_readv
+146	i386	writev			sys_writev			compat_sys_writev
+147	i386	getsid			sys_getsid
+148	i386	fdatasync		sys_fdatasync
+149	i386	_sysctl			sys_sysctl			compat_sys_sysctl
+150	i386	mlock			sys_mlock
+151	i386	munlock			sys_munlock
+152	i386	mlockall		sys_mlockall
+153	i386	munlockall		sys_munlockall
+154	i386	sched_setparam		sys_sched_setparam
+155	i386	sched_getparam		sys_sched_getparam
+156	i386	sched_setscheduler	sys_sched_setscheduler
+157	i386	sched_getscheduler	sys_sched_getscheduler
+158	i386	sched_yield		sys_sched_yield
+159	i386	sched_get_priority_max	sys_sched_get_priority_max
+160	i386	sched_get_priority_min	sys_sched_get_priority_min
+161	i386	sched_rr_get_interval	sys_sched_rr_get_interval	compat_sys_sched_rr_get_interval
+162	i386	nanosleep		sys_nanosleep			compat_sys_nanosleep
+163	i386	mremap			sys_mremap
+164	i386	setresuid		sys_setresuid16
+165	i386	getresuid		sys_getresuid16
+166	i386	vm86			sys_vm86			sys_ni_syscall
+167	i386	query_module
+168	i386	poll			sys_poll
+169	i386	nfsservctl
+170	i386	setresgid		sys_setresgid16
+171	i386	getresgid		sys_getresgid16
+172	i386	prctl			sys_prctl
+173	i386	rt_sigreturn		sys_rt_sigreturn		sys32_rt_sigreturn
+174	i386	rt_sigaction		sys_rt_sigaction		compat_sys_rt_sigaction
+175	i386	rt_sigprocmask		sys_rt_sigprocmask
+176	i386	rt_sigpending		sys_rt_sigpending		compat_sys_rt_sigpending
+177	i386	rt_sigtimedwait		sys_rt_sigtimedwait		compat_sys_rt_sigtimedwait
+178	i386	rt_sigqueueinfo		sys_rt_sigqueueinfo		compat_sys_rt_sigqueueinfo
+179	i386	rt_sigsuspend		sys_rt_sigsuspend
+180	i386	pread64			sys_pread64			sys32_pread
+181	i386	pwrite64		sys_pwrite64			sys32_pwrite
+182	i386	chown			sys_chown16
+183	i386	getcwd			sys_getcwd
+184	i386	capget			sys_capget
+185	i386	capset			sys_capset
+186	i386	sigaltstack		sys_sigaltstack			compat_sys_sigaltstack
+187	i386	sendfile		sys_sendfile			compat_sys_sendfile
+188	i386	getpmsg
+189	i386	putpmsg
+190	i386	vfork			sys_vfork			sys_vfork
+191	i386	ugetrlimit		sys_getrlimit			compat_sys_getrlimit
+192	i386	mmap2			sys_mmap_pgoff
+193	i386	truncate64		sys_truncate64			sys32_truncate64
+194	i386	ftruncate64		sys_ftruncate64			sys32_ftruncate64
+195	i386	stat64			sys_stat64			sys32_stat64
+196	i386	lstat64			sys_lstat64			sys32_lstat64
+197	i386	fstat64			sys_fstat64			sys32_fstat64
+198	i386	lchown32		sys_lchown
+199	i386	getuid32		sys_getuid
+200	i386	getgid32		sys_getgid
+201	i386	geteuid32		sys_geteuid
+202	i386	getegid32		sys_getegid
+203	i386	setreuid32		sys_setreuid
+204	i386	setregid32		sys_setregid
+205	i386	getgroups32		sys_getgroups
+206	i386	setgroups32		sys_setgroups
+207	i386	fchown32		sys_fchown
+208	i386	setresuid32		sys_setresuid
+209	i386	getresuid32		sys_getresuid
+210	i386	setresgid32		sys_setresgid
+211	i386	getresgid32		sys_getresgid
+212	i386	chown32			sys_chown
+213	i386	setuid32		sys_setuid
+214	i386	setgid32		sys_setgid
+215	i386	setfsuid32		sys_setfsuid
+216	i386	setfsgid32		sys_setfsgid
+217	i386	pivot_root		sys_pivot_root
+218	i386	mincore			sys_mincore
+219	i386	madvise			sys_madvise
+220	i386	getdents64		sys_getdents64			compat_sys_getdents64
+221	i386	fcntl64			sys_fcntl64			compat_sys_fcntl64
+# 222 is unused
+# 223 is unused
+224	i386	gettid			sys_gettid
+225	i386	readahead		sys_readahead			sys32_readahead
+226	i386	setxattr		sys_setxattr
+227	i386	lsetxattr		sys_lsetxattr
+228	i386	fsetxattr		sys_fsetxattr
+229	i386	getxattr		sys_getxattr
+230	i386	lgetxattr		sys_lgetxattr
+231	i386	fgetxattr		sys_fgetxattr
+232	i386	listxattr		sys_listxattr
+233	i386	llistxattr		sys_llistxattr
+234	i386	flistxattr		sys_flistxattr
+235	i386	removexattr		sys_removexattr
+236	i386	lremovexattr		sys_lremovexattr
+237	i386	fremovexattr		sys_fremovexattr
+238	i386	tkill			sys_tkill
+239	i386	sendfile64		sys_sendfile64
+240	i386	futex			sys_futex			compat_sys_futex
+241	i386	sched_setaffinity	sys_sched_setaffinity		compat_sys_sched_setaffinity
+242	i386	sched_getaffinity	sys_sched_getaffinity		compat_sys_sched_getaffinity
+243	i386	set_thread_area		sys_set_thread_area
+244	i386	get_thread_area		sys_get_thread_area
+245	i386	io_setup		sys_io_setup			compat_sys_io_setup
+246	i386	io_destroy		sys_io_destroy
+247	i386	io_getevents		sys_io_getevents		compat_sys_io_getevents
+248	i386	io_submit		sys_io_submit			compat_sys_io_submit
+249	i386	io_cancel		sys_io_cancel
+250	i386	fadvise64		sys_fadvise64			sys32_fadvise64
+# 251 is available for reuse (was briefly sys_set_zone_reclaim)
+252	i386	exit_group		sys_exit_group
+253	i386	lookup_dcookie		sys_lookup_dcookie		compat_sys_lookup_dcookie
+254	i386	epoll_create		sys_epoll_create
+255	i386	epoll_ctl		sys_epoll_ctl
+256	i386	epoll_wait		sys_epoll_wait
+257	i386	remap_file_pages	sys_remap_file_pages
+258	i386	set_tid_address		sys_set_tid_address
+259	i386	timer_create		sys_timer_create		compat_sys_timer_create
+260	i386	timer_settime		sys_timer_settime		compat_sys_timer_settime
+261	i386	timer_gettime		sys_timer_gettime		compat_sys_timer_gettime
+262	i386	timer_getoverrun	sys_timer_getoverrun
+263	i386	timer_delete		sys_timer_delete
+264	i386	clock_settime		sys_clock_settime		compat_sys_clock_settime
+265	i386	clock_gettime		sys_clock_gettime		compat_sys_clock_gettime
+266	i386	clock_getres		sys_clock_getres		compat_sys_clock_getres
+267	i386	clock_nanosleep		sys_clock_nanosleep		compat_sys_clock_nanosleep
+268	i386	statfs64		sys_statfs64			compat_sys_statfs64
+269	i386	fstatfs64		sys_fstatfs64			compat_sys_fstatfs64
+270	i386	tgkill			sys_tgkill
+271	i386	utimes			sys_utimes			compat_sys_utimes
+272	i386	fadvise64_64		sys_fadvise64_64		sys32_fadvise64_64
+273	i386	vserver
+274	i386	mbind			sys_mbind
+275	i386	get_mempolicy		sys_get_mempolicy		compat_sys_get_mempolicy
+276	i386	set_mempolicy		sys_set_mempolicy
+277	i386	mq_open			sys_mq_open			compat_sys_mq_open
+278	i386	mq_unlink		sys_mq_unlink
+279	i386	mq_timedsend		sys_mq_timedsend		compat_sys_mq_timedsend
+280	i386	mq_timedreceive		sys_mq_timedreceive		compat_sys_mq_timedreceive
+281	i386	mq_notify		sys_mq_notify			compat_sys_mq_notify
+282	i386	mq_getsetattr		sys_mq_getsetattr		compat_sys_mq_getsetattr
+283	i386	kexec_load		sys_kexec_load			compat_sys_kexec_load
+284	i386	waitid			sys_waitid			compat_sys_waitid
+# 285 sys_setaltroot
+286	i386	add_key			sys_add_key
+287	i386	request_key		sys_request_key
+288	i386	keyctl			sys_keyctl
+289	i386	ioprio_set		sys_ioprio_set
+290	i386	ioprio_get		sys_ioprio_get
+291	i386	inotify_init		sys_inotify_init
+292	i386	inotify_add_watch	sys_inotify_add_watch
+293	i386	inotify_rm_watch	sys_inotify_rm_watch
+294	i386	migrate_pages		sys_migrate_pages
+295	i386	openat			sys_openat			compat_sys_openat
+296	i386	mkdirat			sys_mkdirat
+297	i386	mknodat			sys_mknodat
+298	i386	fchownat		sys_fchownat
+299	i386	futimesat		sys_futimesat			compat_sys_futimesat
+300	i386	fstatat64		sys_fstatat64			sys32_fstatat
+301	i386	unlinkat		sys_unlinkat
+302	i386	renameat		sys_renameat
+303	i386	linkat			sys_linkat
+304	i386	symlinkat		sys_symlinkat
+305	i386	readlinkat		sys_readlinkat
+306	i386	fchmodat		sys_fchmodat
+307	i386	faccessat		sys_faccessat
+308	i386	pselect6		sys_pselect6			compat_sys_pselect6
+309	i386	ppoll			sys_ppoll			compat_sys_ppoll
+310	i386	unshare			sys_unshare
+311	i386	set_robust_list		sys_set_robust_list		compat_sys_set_robust_list
+312	i386	get_robust_list		sys_get_robust_list		compat_sys_get_robust_list
+313	i386	splice			sys_splice
+314	i386	sync_file_range		sys_sync_file_range		sys32_sync_file_range
+315	i386	tee			sys_tee
+316	i386	vmsplice		sys_vmsplice			compat_sys_vmsplice
+317	i386	move_pages		sys_move_pages			compat_sys_move_pages
+318	i386	getcpu			sys_getcpu
+319	i386	epoll_pwait		sys_epoll_pwait
+320	i386	utimensat		sys_utimensat			compat_sys_utimensat
+321	i386	signalfd		sys_signalfd			compat_sys_signalfd
+322	i386	timerfd_create		sys_timerfd_create
+323	i386	eventfd			sys_eventfd
+324	i386	fallocate		sys_fallocate			sys32_fallocate
+325	i386	timerfd_settime		sys_timerfd_settime		compat_sys_timerfd_settime
+326	i386	timerfd_gettime		sys_timerfd_gettime		compat_sys_timerfd_gettime
+327	i386	signalfd4		sys_signalfd4			compat_sys_signalfd4
+328	i386	eventfd2		sys_eventfd2
+329	i386	epoll_create1		sys_epoll_create1
+330	i386	dup3			sys_dup3
+331	i386	pipe2			sys_pipe2
+332	i386	inotify_init1		sys_inotify_init1
+333	i386	preadv			sys_preadv			compat_sys_preadv
+334	i386	pwritev			sys_pwritev			compat_sys_pwritev
+335	i386	rt_tgsigqueueinfo	sys_rt_tgsigqueueinfo		compat_sys_rt_tgsigqueueinfo
+336	i386	perf_event_open		sys_perf_event_open
+337	i386	recvmmsg		sys_recvmmsg			compat_sys_recvmmsg
+338	i386	fanotify_init		sys_fanotify_init
+339	i386	fanotify_mark		sys_fanotify_mark		compat_sys_fanotify_mark
+340	i386	prlimit64		sys_prlimit64
+341	i386	name_to_handle_at	sys_name_to_handle_at
+342	i386	open_by_handle_at	sys_open_by_handle_at		compat_sys_open_by_handle_at
+343	i386	clock_adjtime		sys_clock_adjtime		compat_sys_clock_adjtime
+344	i386	syncfs			sys_syncfs
+345	i386	sendmmsg		sys_sendmmsg			compat_sys_sendmmsg
+346	i386	setns			sys_setns
+347	i386	process_vm_readv	sys_process_vm_readv		compat_sys_process_vm_readv
+348	i386	process_vm_writev	sys_process_vm_writev		compat_sys_process_vm_writev
+349	i386	kcmp			sys_kcmp
+350	i386	finit_module		sys_finit_module
+351	i386	sched_setattr		sys_sched_setattr
+352	i386	sched_getattr		sys_sched_getattr
+353	i386	renameat2		sys_renameat2
+354	i386	seccomp			sys_seccomp
+355	i386	getrandom		sys_getrandom
+356	i386	memfd_create		sys_memfd_create
+357	i386	bpf			sys_bpf
+358	i386	execveat		sys_execveat			compat_sys_execveat
+359	i386	socket			sys_socket
+360	i386	socketpair		sys_socketpair
+361	i386	bind			sys_bind
+362	i386	connect			sys_connect
+363	i386	listen			sys_listen
+364	i386	accept4			sys_accept4
+365	i386	getsockopt		sys_getsockopt			compat_sys_getsockopt
+366	i386	setsockopt		sys_setsockopt			compat_sys_setsockopt
+367	i386	getsockname		sys_getsockname
+368	i386	getpeername		sys_getpeername
+369	i386	sendto			sys_sendto
+370	i386	sendmsg			sys_sendmsg			compat_sys_sendmsg
+371	i386	recvfrom		sys_recvfrom			compat_sys_recvfrom
+372	i386	recvmsg			sys_recvmsg			compat_sys_recvmsg
+373	i386	shutdown		sys_shutdown
+374	i386	userfaultfd		sys_userfaultfd
+375	i386	membarrier		sys_membarrier
+376	i386	mlock2			sys_mlock2
diff --git a/kernel/arch/x86/entry/syscalls/syscall_64.tbl b/kernel/arch/x86/entry/syscalls/syscall_64.tbl
new file mode 100644
index 000000000..314a90bfc
--- /dev/null
+++ b/kernel/arch/x86/entry/syscalls/syscall_64.tbl
@@ -0,0 +1,373 @@
+#
+# 64-bit system call numbers and entry vectors
+#
+# The format is:
+# <number> <abi> <name> <entry point>
+#
+# The abi is "common", "64" or "x32" for this file.
+#
+0	common	read			sys_read
+1	common	write			sys_write
+2	common	open			sys_open
+3	common	close			sys_close
+4	common	stat			sys_newstat
+5	common	fstat			sys_newfstat
+6	common	lstat			sys_newlstat
+7	common	poll			sys_poll
+8	common	lseek			sys_lseek
+9	common	mmap			sys_mmap
+10	common	mprotect		sys_mprotect
+11	common	munmap			sys_munmap
+12	common	brk			sys_brk
+13	64	rt_sigaction		sys_rt_sigaction
+14	common	rt_sigprocmask		sys_rt_sigprocmask
+15	64	rt_sigreturn		stub_rt_sigreturn
+16	64	ioctl			sys_ioctl
+17	common	pread64			sys_pread64
+18	common	pwrite64		sys_pwrite64
+19	64	readv			sys_readv
+20	64	writev			sys_writev
+21	common	access			sys_access
+22	common	pipe			sys_pipe
+23	common	select			sys_select
+24	common	sched_yield		sys_sched_yield
+25	common	mremap			sys_mremap
+26	common	msync			sys_msync
+27	common	mincore			sys_mincore
+28	common	madvise			sys_madvise
+29	common	shmget			sys_shmget
+30	common	shmat			sys_shmat
+31	common	shmctl			sys_shmctl
+32	common	dup			sys_dup
+33	common	dup2			sys_dup2
+34	common	pause			sys_pause
+35	common	nanosleep		sys_nanosleep
+36	common	getitimer		sys_getitimer
+37	common	alarm			sys_alarm
+38	common	setitimer		sys_setitimer
+39	common	getpid			sys_getpid
+40	common	sendfile		sys_sendfile64
+41	common	socket			sys_socket
+42	common	connect			sys_connect
+43	common	accept			sys_accept
+44	common	sendto			sys_sendto
+45	64	recvfrom		sys_recvfrom
+46	64	sendmsg			sys_sendmsg
+47	64	recvmsg			sys_recvmsg
+48	common	shutdown		sys_shutdown
+49	common	bind			sys_bind
+50	common	listen			sys_listen
+51	common	getsockname		sys_getsockname
+52	common	getpeername		sys_getpeername
+53	common	socketpair		sys_socketpair
+54	64	setsockopt		sys_setsockopt
+55	64	getsockopt		sys_getsockopt
+56	common	clone			stub_clone
+57	common	fork			stub_fork
+58	common	vfork			stub_vfork
+59	64	execve			stub_execve
+60	common	exit			sys_exit
+61	common	wait4			sys_wait4
+62	common	kill			sys_kill
+63	common	uname			sys_newuname
+64	common	semget			sys_semget
+65	common	semop			sys_semop
+66	common	semctl			sys_semctl
+67	common	shmdt			sys_shmdt
+68	common	msgget			sys_msgget
+69	common	msgsnd			sys_msgsnd
+70	common	msgrcv			sys_msgrcv
+71	common	msgctl			sys_msgctl
+72	common	fcntl			sys_fcntl
+73	common	flock			sys_flock
+74	common	fsync			sys_fsync
+75	common	fdatasync		sys_fdatasync
+76	common	truncate		sys_truncate
+77	common	ftruncate		sys_ftruncate
+78	common	getdents		sys_getdents
+79	common	getcwd			sys_getcwd
+80	common	chdir			sys_chdir
+81	common	fchdir			sys_fchdir
+82	common	rename			sys_rename
+83	common	mkdir			sys_mkdir
+84	common	rmdir			sys_rmdir
+85	common	creat			sys_creat
+86	common	link			sys_link
+87	common	unlink			sys_unlink
+88	common	symlink			sys_symlink
+89	common	readlink		sys_readlink
+90	common	chmod			sys_chmod
+91	common	fchmod			sys_fchmod
+92	common	chown			sys_chown
+93	common	fchown			sys_fchown
+94	common	lchown			sys_lchown
+95	common	umask			sys_umask
+96	common	gettimeofday		sys_gettimeofday
+97	common	getrlimit		sys_getrlimit
+98	common	getrusage		sys_getrusage
+99	common	sysinfo			sys_sysinfo
+100	common	times			sys_times
+101	64	ptrace			sys_ptrace
+102	common	getuid			sys_getuid
+103	common	syslog			sys_syslog
+104	common	getgid			sys_getgid
+105	common	setuid			sys_setuid
+106	common	setgid			sys_setgid
+107	common	geteuid			sys_geteuid
+108	common	getegid			sys_getegid
+109	common	setpgid			sys_setpgid
+110	common	getppid			sys_getppid
+111	common	getpgrp			sys_getpgrp
+112	common	setsid			sys_setsid
+113	common	setreuid		sys_setreuid
+114	common	setregid		sys_setregid
+115	common	getgroups		sys_getgroups
+116	common	setgroups		sys_setgroups
+117	common	setresuid		sys_setresuid
+118	common	getresuid		sys_getresuid
+119	common	setresgid		sys_setresgid
+120	common	getresgid		sys_getresgid
+121	common	getpgid			sys_getpgid
+122	common	setfsuid		sys_setfsuid
+123	common	setfsgid		sys_setfsgid
+124	common	getsid			sys_getsid
+125	common	capget			sys_capget
+126	common	capset			sys_capset
+127	64	rt_sigpending		sys_rt_sigpending
+128	64	rt_sigtimedwait		sys_rt_sigtimedwait
+129	64	rt_sigqueueinfo		sys_rt_sigqueueinfo
+130	common	rt_sigsuspend		sys_rt_sigsuspend
+131	64	sigaltstack		sys_sigaltstack
+132	common	utime			sys_utime
+133	common	mknod			sys_mknod
+134	64	uselib
+135	common	personality		sys_personality
+136	common	ustat			sys_ustat
+137	common	statfs			sys_statfs
+138	common	fstatfs			sys_fstatfs
+139	common	sysfs			sys_sysfs
+140	common	getpriority		sys_getpriority
+141	common	setpriority		sys_setpriority
+142	common	sched_setparam		sys_sched_setparam
+143	common	sched_getparam		sys_sched_getparam
+144	common	sched_setscheduler	sys_sched_setscheduler
+145	common	sched_getscheduler	sys_sched_getscheduler
+146	common	sched_get_priority_max	sys_sched_get_priority_max
+147	common	sched_get_priority_min	sys_sched_get_priority_min
+148	common	sched_rr_get_interval	sys_sched_rr_get_interval
+149	common	mlock			sys_mlock
+150	common	munlock			sys_munlock
+151	common	mlockall		sys_mlockall
+152	common	munlockall		sys_munlockall
+153	common	vhangup			sys_vhangup
+154	common	modify_ldt		sys_modify_ldt
+155	common	pivot_root		sys_pivot_root
+156	64	_sysctl			sys_sysctl
+157	common	prctl			sys_prctl
+158	common	arch_prctl		sys_arch_prctl
+159	common	adjtimex		sys_adjtimex
+160	common	setrlimit		sys_setrlimit
+161	common	chroot			sys_chroot
+162	common	sync			sys_sync
+163	common	acct			sys_acct
+164	common	settimeofday		sys_settimeofday
+165	common	mount			sys_mount
+166	common	umount2			sys_umount
+167	common	swapon			sys_swapon
+168	common	swapoff			sys_swapoff
+169	common	reboot			sys_reboot
+170	common	sethostname		sys_sethostname
+171	common	setdomainname		sys_setdomainname
+172	common	iopl			sys_iopl
+173	common	ioperm			sys_ioperm
+174	64	create_module
+175	common	init_module		sys_init_module
+176	common	delete_module		sys_delete_module
+177	64	get_kernel_syms
+178	64	query_module
+179	common	quotactl		sys_quotactl
+180	64	nfsservctl
+181	common	getpmsg
+182	common	putpmsg
+183	common	afs_syscall
+184	common	tuxcall
+185	common	security
+186	common	gettid			sys_gettid
+187	common	readahead		sys_readahead
+188	common	setxattr		sys_setxattr
+189	common	lsetxattr		sys_lsetxattr
+190	common	fsetxattr		sys_fsetxattr
+191	common	getxattr		sys_getxattr
+192	common	lgetxattr		sys_lgetxattr
+193	common	fgetxattr		sys_fgetxattr
+194	common	listxattr		sys_listxattr
+195	common	llistxattr		sys_llistxattr
+196	common	flistxattr		sys_flistxattr
+197	common	removexattr		sys_removexattr
+198	common	lremovexattr		sys_lremovexattr
+199	common	fremovexattr		sys_fremovexattr
+200	common	tkill			sys_tkill
+201	common	time			sys_time
+202	common	futex			sys_futex
+203	common	sched_setaffinity	sys_sched_setaffinity
+204	common	sched_getaffinity	sys_sched_getaffinity
+205	64	set_thread_area
+206	64	io_setup		sys_io_setup
+207	common	io_destroy		sys_io_destroy
+208	common	io_getevents		sys_io_getevents
+209	64	io_submit		sys_io_submit
+210	common	io_cancel		sys_io_cancel
+211	64	get_thread_area
+212	common	lookup_dcookie		sys_lookup_dcookie
+213	common	epoll_create		sys_epoll_create
+214	64	epoll_ctl_old
+215	64	epoll_wait_old
+216	common	remap_file_pages	sys_remap_file_pages
+217	common	getdents64		sys_getdents64
+218	common	set_tid_address		sys_set_tid_address
+219	common	restart_syscall		sys_restart_syscall
+220	common	semtimedop		sys_semtimedop
+221	common	fadvise64		sys_fadvise64
+222	64	timer_create		sys_timer_create
+223	common	timer_settime		sys_timer_settime
+224	common	timer_gettime		sys_timer_gettime
+225	common	timer_getoverrun	sys_timer_getoverrun
+226	common	timer_delete		sys_timer_delete
+227	common	clock_settime		sys_clock_settime
+228	common	clock_gettime		sys_clock_gettime
+229	common	clock_getres		sys_clock_getres
+230	common	clock_nanosleep		sys_clock_nanosleep
+231	common	exit_group		sys_exit_group
+232	common	epoll_wait		sys_epoll_wait
+233	common	epoll_ctl		sys_epoll_ctl
+234	common	tgkill			sys_tgkill
+235	common	utimes			sys_utimes
+236	64	vserver
+237	common	mbind			sys_mbind
+238	common	set_mempolicy		sys_set_mempolicy
+239	common	get_mempolicy		sys_get_mempolicy
+240	common	mq_open			sys_mq_open
+241	common	mq_unlink		sys_mq_unlink
+242	common	mq_timedsend		sys_mq_timedsend
+243	common	mq_timedreceive		sys_mq_timedreceive
+244	64	mq_notify		sys_mq_notify
+245	common	mq_getsetattr		sys_mq_getsetattr
+246	64	kexec_load		sys_kexec_load
+247	64	waitid			sys_waitid
+248	common	add_key			sys_add_key
+249	common	request_key		sys_request_key
+250	common	keyctl			sys_keyctl
+251	common	ioprio_set		sys_ioprio_set
+252	common	ioprio_get		sys_ioprio_get
+253	common	inotify_init		sys_inotify_init
+254	common	inotify_add_watch	sys_inotify_add_watch
+255	common	inotify_rm_watch	sys_inotify_rm_watch
+256	common	migrate_pages		sys_migrate_pages
+257	common	openat			sys_openat
+258	common	mkdirat			sys_mkdirat
+259	common	mknodat			sys_mknodat
+260	common	fchownat		sys_fchownat
+261	common	futimesat		sys_futimesat
+262	common	newfstatat		sys_newfstatat
+263	common	unlinkat		sys_unlinkat
+264	common	renameat		sys_renameat
+265	common	linkat			sys_linkat
+266	common	symlinkat		sys_symlinkat
+267	common	readlinkat		sys_readlinkat
+268	common	fchmodat		sys_fchmodat
+269	common	faccessat		sys_faccessat
+270	common	pselect6		sys_pselect6
+271	common	ppoll			sys_ppoll
+272	common	unshare			sys_unshare
+273	64	set_robust_list		sys_set_robust_list
+274	64	get_robust_list		sys_get_robust_list
+275	common	splice			sys_splice
+276	common	tee			sys_tee
+277	common	sync_file_range		sys_sync_file_range
+278	64	vmsplice		sys_vmsplice
+279	64	move_pages		sys_move_pages
+280	common	utimensat		sys_utimensat
+281	common	epoll_pwait		sys_epoll_pwait
+282	common	signalfd		sys_signalfd
+283	common	timerfd_create		sys_timerfd_create
+284	common	eventfd			sys_eventfd
+285	common	fallocate		sys_fallocate
+286	common	timerfd_settime		sys_timerfd_settime
+287	common	timerfd_gettime		sys_timerfd_gettime
+288	common	accept4			sys_accept4
+289	common	signalfd4		sys_signalfd4
+290	common	eventfd2		sys_eventfd2
+291	common	epoll_create1		sys_epoll_create1
+292	common	dup3			sys_dup3
+293	common	pipe2			sys_pipe2
+294	common	inotify_init1		sys_inotify_init1
+295	64	preadv			sys_preadv
+296	64	pwritev			sys_pwritev
+297	64	rt_tgsigqueueinfo	sys_rt_tgsigqueueinfo
+298	common	perf_event_open		sys_perf_event_open
+299	64	recvmmsg		sys_recvmmsg
+300	common	fanotify_init		sys_fanotify_init
+301	common	fanotify_mark		sys_fanotify_mark
+302	common	prlimit64		sys_prlimit64
+303	common	name_to_handle_at	sys_name_to_handle_at
+304	common	open_by_handle_at	sys_open_by_handle_at
+305	common	clock_adjtime		sys_clock_adjtime
+306	common	syncfs			sys_syncfs
+307	64	sendmmsg		sys_sendmmsg
+308	common	setns			sys_setns
+309	common	getcpu			sys_getcpu
+310	64	process_vm_readv	sys_process_vm_readv
+311	64	process_vm_writev	sys_process_vm_writev
+312	common	kcmp			sys_kcmp
+313	common	finit_module		sys_finit_module
+314	common	sched_setattr		sys_sched_setattr
+315	common	sched_getattr		sys_sched_getattr
+316	common	renameat2		sys_renameat2
+317	common	seccomp			sys_seccomp
+318	common	getrandom		sys_getrandom
+319	common	memfd_create		sys_memfd_create
+320	common	kexec_file_load		sys_kexec_file_load
+321	common	bpf			sys_bpf
+322	64	execveat		stub_execveat
+323	common	userfaultfd		sys_userfaultfd
+324	common	membarrier		sys_membarrier
+325	common	mlock2			sys_mlock2
+
+#
+# x32-specific system call numbers start at 512 to avoid cache impact
+# for native 64-bit operation.
+#
+512	x32	rt_sigaction		compat_sys_rt_sigaction
+513	x32	rt_sigreturn		stub_x32_rt_sigreturn
+514	x32	ioctl			compat_sys_ioctl
+515	x32	readv			compat_sys_readv
+516	x32	writev			compat_sys_writev
+517	x32	recvfrom		compat_sys_recvfrom
+518	x32	sendmsg			compat_sys_sendmsg
+519	x32	recvmsg			compat_sys_recvmsg
+520	x32	execve			stub_x32_execve
+521	x32	ptrace			compat_sys_ptrace
+522	x32	rt_sigpending		compat_sys_rt_sigpending
+523	x32	rt_sigtimedwait		compat_sys_rt_sigtimedwait
+524	x32	rt_sigqueueinfo		compat_sys_rt_sigqueueinfo
+525	x32	sigaltstack		compat_sys_sigaltstack
+526	x32	timer_create		compat_sys_timer_create
+527	x32	mq_notify		compat_sys_mq_notify
+528	x32	kexec_load		compat_sys_kexec_load
+529	x32	waitid			compat_sys_waitid
+530	x32	set_robust_list		compat_sys_set_robust_list
+531	x32	get_robust_list		compat_sys_get_robust_list
+532	x32	vmsplice		compat_sys_vmsplice
+533	x32	move_pages		compat_sys_move_pages
+534	x32	preadv			compat_sys_preadv64
+535	x32	pwritev			compat_sys_pwritev64
+536	x32	rt_tgsigqueueinfo	compat_sys_rt_tgsigqueueinfo
+537	x32	recvmmsg		compat_sys_recvmmsg
+538	x32	sendmmsg		compat_sys_sendmmsg
+539	x32	process_vm_readv	compat_sys_process_vm_readv
+540	x32	process_vm_writev	compat_sys_process_vm_writev
+541	x32	setsockopt		compat_sys_setsockopt
+542	x32	getsockopt		compat_sys_getsockopt
+543	x32	io_setup		compat_sys_io_setup
+544	x32	io_submit		compat_sys_io_submit
+545	x32	execveat		stub_x32_execveat
diff --git a/kernel/arch/x86/entry/syscalls/syscallhdr.sh b/kernel/arch/x86/entry/syscalls/syscallhdr.sh
new file mode 100644
index 000000000..31fd5f1f3
--- /dev/null
+++ b/kernel/arch/x86/entry/syscalls/syscallhdr.sh
@@ -0,0 +1,27 @@
+#!/bin/sh
+
+in="$1"
+out="$2"
+my_abis=`echo "($3)" | tr ',' '|'`
+prefix="$4"
+offset="$5"
+
+fileguard=_ASM_X86_`basename "$out" | sed \
+    -e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/' \
+    -e 's/[^A-Z0-9_]/_/g' -e 's/__/_/g'`
+grep -E "^[0-9A-Fa-fXx]+[[:space:]]+${my_abis}" "$in" | sort -n | (
+    echo "#ifndef ${fileguard}"
+    echo "#define ${fileguard} 1"
+    echo ""
+
+    while read nr abi name entry ; do
+	if [ -z "$offset" ]; then
+	    echo "#define __NR_${prefix}${name} $nr"
+	else
+	    echo "#define __NR_${prefix}${name} ($offset + $nr)"
+        fi
+    done
+
+    echo ""
+    echo "#endif /* ${fileguard} */"
+) > "$out"
diff --git a/kernel/arch/x86/entry/syscalls/syscalltbl.sh b/kernel/arch/x86/entry/syscalls/syscalltbl.sh
new file mode 100644
index 000000000..0e7f8ec07
--- /dev/null
+++ b/kernel/arch/x86/entry/syscalls/syscalltbl.sh
@@ -0,0 +1,15 @@
+#!/bin/sh
+
+in="$1"
+out="$2"
+
+grep '^[0-9]' "$in" | sort -n | (
+    while read nr abi name entry compat; do
+	abi=`echo "$abi" | tr '[a-z]' '[A-Z]'`
+	if [ -n "$compat" ]; then
+	    echo "__SYSCALL_${abi}($nr, $entry, $compat)"
+	elif [ -n "$entry" ]; then
+	    echo "__SYSCALL_${abi}($nr, $entry, $entry)"
+	fi
+    done
+) > "$out"
diff --git a/kernel/arch/x86/entry/thunk_32.S b/kernel/arch/x86/entry/thunk_32.S
new file mode 100644
index 000000000..e5a17114a
--- /dev/null
+++ b/kernel/arch/x86/entry/thunk_32.S
@@ -0,0 +1,40 @@
+/*
+ * Trampoline to trace irqs off. (otherwise CALLER_ADDR1 might crash)
+ * Copyright 2008 by Steven Rostedt, Red Hat, Inc
+ *  (inspired by Andi Kleen's thunk_64.S)
+ * Subject to the GNU public license, v.2. No warranty of any kind.
+ */
+	#include <linux/linkage.h>
+	#include <asm/asm.h>
+
+	/* put return address in eax (arg1) */
+	.macro THUNK name, func, put_ret_addr_in_eax=0
+	.globl \name
+\name:
+	pushl %eax
+	pushl %ecx
+	pushl %edx
+
+	.if \put_ret_addr_in_eax
+	/* Place EIP in the arg1 */
+	movl 3*4(%esp), %eax
+	.endif
+
+	call \func
+	popl %edx
+	popl %ecx
+	popl %eax
+	ret
+	_ASM_NOKPROBE(\name)
+	.endm
+
+#ifdef CONFIG_TRACE_IRQFLAGS
+	THUNK trace_hardirqs_on_thunk,trace_hardirqs_on_caller,1
+	THUNK trace_hardirqs_off_thunk,trace_hardirqs_off_caller,1
+#endif
+
+#ifdef CONFIG_PREEMPT
+	THUNK ___preempt_schedule, preempt_schedule
+	THUNK ___preempt_schedule_notrace, preempt_schedule_notrace
+#endif
+
diff --git a/kernel/arch/x86/entry/thunk_64.S b/kernel/arch/x86/entry/thunk_64.S
new file mode 100644
index 000000000..efb2b932b
--- /dev/null
+++ b/kernel/arch/x86/entry/thunk_64.S
@@ -0,0 +1,67 @@
+/*
+ * Save registers before calling assembly functions. This avoids
+ * disturbance of register allocation in some inline assembly constructs.
+ * Copyright 2001,2002 by Andi Kleen, SuSE Labs.
+ * Added trace_hardirqs callers - Copyright 2007 Steven Rostedt, Red Hat, Inc.
+ * Subject to the GNU public license, v.2. No warranty of any kind.
+ */
+#include <linux/linkage.h>
+#include "calling.h"
+#include <asm/asm.h>
+
+	/* rdi:	arg1 ... normal C conventions. rax is saved/restored. */
+	.macro THUNK name, func, put_ret_addr_in_rdi=0
+	.globl \name
+\name:
+
+	/* this one pushes 9 elems, the next one would be %rIP */
+	pushq %rdi
+	pushq %rsi
+	pushq %rdx
+	pushq %rcx
+	pushq %rax
+	pushq %r8
+	pushq %r9
+	pushq %r10
+	pushq %r11
+
+	.if \put_ret_addr_in_rdi
+	/* 9*8(%rsp) is return addr on stack */
+	movq 9*8(%rsp), %rdi
+	.endif
+
+	call \func
+	jmp  restore
+	_ASM_NOKPROBE(\name)
+	.endm
+
+#ifdef CONFIG_TRACE_IRQFLAGS
+	THUNK trace_hardirqs_on_thunk,trace_hardirqs_on_caller,1
+	THUNK trace_hardirqs_off_thunk,trace_hardirqs_off_caller,1
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	THUNK lockdep_sys_exit_thunk,lockdep_sys_exit
+#endif
+
+#ifdef CONFIG_PREEMPT
+	THUNK ___preempt_schedule, preempt_schedule
+	THUNK ___preempt_schedule_notrace, preempt_schedule_notrace
+#endif
+
+#if defined(CONFIG_TRACE_IRQFLAGS) \
+ || defined(CONFIG_DEBUG_LOCK_ALLOC) \
+ || defined(CONFIG_PREEMPT)
+restore:
+	popq %r11
+	popq %r10
+	popq %r9
+	popq %r8
+	popq %rax
+	popq %rcx
+	popq %rdx
+	popq %rsi
+	popq %rdi
+	ret
+	_ASM_NOKPROBE(restore)
+#endif
diff --git a/kernel/arch/x86/entry/vdso/.gitignore b/kernel/arch/x86/entry/vdso/.gitignore
new file mode 100644
index 000000000..aae8ffdd5
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/.gitignore
@@ -0,0 +1,7 @@
+vdso.lds
+vdsox32.lds
+vdso32-syscall-syms.lds
+vdso32-sysenter-syms.lds
+vdso32-int80-syms.lds
+vdso-image-*.c
+vdso2c
diff --git a/kernel/arch/x86/entry/vdso/Makefile b/kernel/arch/x86/entry/vdso/Makefile
new file mode 100644
index 000000000..265c0ed68
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/Makefile
@@ -0,0 +1,196 @@
+#
+# Building vDSO images for x86.
+#
+
+KBUILD_CFLAGS += $(DISABLE_LTO)
+KASAN_SANITIZE := n
+
+VDSO64-$(CONFIG_X86_64)		:= y
+VDSOX32-$(CONFIG_X86_X32_ABI)	:= y
+VDSO32-$(CONFIG_X86_32)		:= y
+VDSO32-$(CONFIG_IA32_EMULATION)	:= y
+
+# files to link into the vdso
+vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o
+
+# files to link into kernel
+obj-y				+= vma.o
+
+# vDSO images to build
+vdso_img-$(VDSO64-y)		+= 64
+vdso_img-$(VDSOX32-y)		+= x32
+vdso_img-$(VDSO32-y)		+= 32
+
+obj-$(VDSO32-y)			+= vdso32-setup.o
+
+vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
+
+$(obj)/vdso.o: $(obj)/vdso.so
+
+targets += vdso.lds $(vobjs-y)
+
+# Build the vDSO image C files and link them in.
+vdso_img_objs := $(vdso_img-y:%=vdso-image-%.o)
+vdso_img_cfiles := $(vdso_img-y:%=vdso-image-%.c)
+vdso_img_sodbg := $(vdso_img-y:%=vdso%.so.dbg)
+obj-y += $(vdso_img_objs)
+targets += $(vdso_img_cfiles)
+targets += $(vdso_img_sodbg)
+.SECONDARY: $(vdso_img-y:%=$(obj)/vdso-image-%.c) \
+	$(vdso_img-y:%=$(obj)/vdso%.so)
+
+export CPPFLAGS_vdso.lds += -P -C
+
+VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \
+			-Wl,--no-undefined \
+			-Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096 \
+			$(DISABLE_LTO)
+
+$(obj)/vdso64.so.dbg: $(src)/vdso.lds $(vobjs) FORCE
+	$(call if_changed,vdso)
+
+HOST_EXTRACFLAGS += -I$(srctree)/tools/include -I$(srctree)/include/uapi -I$(srctree)/arch/x86/include/uapi
+hostprogs-y			+= vdso2c
+
+quiet_cmd_vdso2c = VDSO2C  $@
+define cmd_vdso2c
+	$(obj)/vdso2c $< $(<:%.dbg=%) $@
+endef
+
+$(obj)/vdso-image-%.c: $(obj)/vdso%.so.dbg $(obj)/vdso%.so $(obj)/vdso2c FORCE
+	$(call if_changed,vdso2c)
+
+#
+# Don't omit frame pointers for ease of userspace debugging, but do
+# optimize sibling calls.
+#
+CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
+       $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \
+       -fno-omit-frame-pointer -foptimize-sibling-calls \
+       -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO
+
+$(vobjs): KBUILD_CFLAGS += $(CFL)
+
+#
+# vDSO code runs in userspace and -pg doesn't help with profiling anyway.
+#
+CFLAGS_REMOVE_vdso-note.o = -pg
+CFLAGS_REMOVE_vclock_gettime.o = -pg
+CFLAGS_REMOVE_vgetcpu.o = -pg
+CFLAGS_REMOVE_vvar.o = -pg
+
+#
+# X32 processes use x32 vDSO to access 64bit kernel data.
+#
+# Build x32 vDSO image:
+# 1. Compile x32 vDSO as 64bit.
+# 2. Convert object files to x32.
+# 3. Build x32 VDSO image with x32 objects, which contains 64bit codes
+# so that it can reach 64bit address space with 64bit pointers.
+#
+
+CPPFLAGS_vdsox32.lds = $(CPPFLAGS_vdso.lds)
+VDSO_LDFLAGS_vdsox32.lds = -Wl,-m,elf32_x86_64 \
+			   -Wl,-soname=linux-vdso.so.1 \
+			   -Wl,-z,max-page-size=4096 \
+			   -Wl,-z,common-page-size=4096
+
+# 64-bit objects to re-brand as x32
+vobjs64-for-x32 := $(filter-out $(vobjs-nox32),$(vobjs-y))
+
+# x32-rebranded versions
+vobjx32s-y := $(vobjs64-for-x32:.o=-x32.o)
+
+# same thing, but in the output directory
+vobjx32s := $(foreach F,$(vobjx32s-y),$(obj)/$F)
+
+# Convert 64bit object file to x32 for x32 vDSO.
+quiet_cmd_x32 = X32     $@
+      cmd_x32 = $(OBJCOPY) -O elf32-x86-64 $< $@
+
+$(obj)/%-x32.o: $(obj)/%.o FORCE
+	$(call if_changed,x32)
+
+targets += vdsox32.lds $(vobjx32s-y)
+
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg
+	$(call if_changed,objcopy)
+
+$(obj)/vdsox32.so.dbg: $(src)/vdsox32.lds $(vobjx32s) FORCE
+	$(call if_changed,vdso)
+
+CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds)
+VDSO_LDFLAGS_vdso32.lds = -m32 -Wl,-m,elf_i386 -Wl,-soname=linux-gate.so.1
+
+# This makes sure the $(obj) subdirectory exists even though vdso32/
+# is not a kbuild sub-make subdirectory.
+override obj-dirs = $(dir $(obj)) $(obj)/vdso32/
+
+targets += vdso32/vdso32.lds
+targets += vdso32/note.o vdso32/vclock_gettime.o vdso32/system_call.o
+targets += vdso32/vclock_gettime.o
+
+KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS)) -DBUILD_VDSO
+$(obj)/vdso32.so.dbg: KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
+$(obj)/vdso32.so.dbg: asflags-$(CONFIG_X86_64) += -m32
+
+KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS))
+KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32))
+KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32))
+KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32))
+KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic
+KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector)
+KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls)
+KBUILD_CFLAGS_32 += -fno-omit-frame-pointer
+KBUILD_CFLAGS_32 += -DDISABLE_BRANCH_PROFILING
+$(obj)/vdso32.so.dbg: KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)
+
+$(obj)/vdso32.so.dbg: FORCE \
+		      $(obj)/vdso32/vdso32.lds \
+		      $(obj)/vdso32/vclock_gettime.o \
+		      $(obj)/vdso32/note.o \
+		      $(obj)/vdso32/system_call.o
+	$(call if_changed,vdso)
+
+#
+# The DSO images are built using a special linker script.
+#
+quiet_cmd_vdso = VDSO    $@
+      cmd_vdso = $(CC) -nostdlib -o $@ \
+		       $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
+		       -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \
+		 sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'
+
+VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=both) \
+	$(call cc-ldoption, -Wl$(comma)--build-id) -Wl,-Bsymbolic $(LTO_CFLAGS)
+GCOV_PROFILE := n
+
+#
+# Install the unstripped copies of vdso*.so.  If our toolchain supports
+# build-id, install .build-id links as well.
+#
+quiet_cmd_vdso_install = INSTALL $(@:install_%=%)
+define cmd_vdso_install
+	cp $< "$(MODLIB)/vdso/$(@:install_%=%)"; \
+	if readelf -n $< |grep -q 'Build ID'; then \
+	  buildid=`readelf -n $< |grep 'Build ID' |sed -e 's/^.*Build ID: \(.*\)$$/\1/'`; \
+	  first=`echo $$buildid | cut -b-2`; \
+	  last=`echo $$buildid | cut -b3-`; \
+	  mkdir -p "$(MODLIB)/vdso/.build-id/$$first"; \
+	  ln -sf "../../$(@:install_%=%)" "$(MODLIB)/vdso/.build-id/$$first/$$last.debug"; \
+	fi
+endef
+
+vdso_img_insttargets := $(vdso_img_sodbg:%.dbg=install_%)
+
+$(MODLIB)/vdso: FORCE
+	@mkdir -p $(MODLIB)/vdso
+
+$(vdso_img_insttargets): install_%: $(obj)/%.dbg $(MODLIB)/vdso FORCE
+	$(call cmd,vdso_install)
+
+PHONY += vdso_install $(vdso_img_insttargets)
+vdso_install: $(vdso_img_insttargets) FORCE
+
+clean-files := vdso32.so vdso32.so.dbg vdso64* vdso-image-*.c vdsox32.so*
diff --git a/kernel/arch/x86/entry/vdso/checkundef.sh b/kernel/arch/x86/entry/vdso/checkundef.sh
new file mode 100755
index 000000000..7ee90a9b5
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/checkundef.sh
@@ -0,0 +1,10 @@
+#!/bin/sh
+nm="$1"
+file="$2"
+$nm "$file" | grep '^ *U' > /dev/null 2>&1
+if [ $? -eq 1 ]; then
+    exit 0
+else
+    echo "$file: undefined symbols found" >&2
+    exit 1
+fi
diff --git a/kernel/arch/x86/entry/vdso/vclock_gettime.c b/kernel/arch/x86/entry/vdso/vclock_gettime.c
new file mode 100644
index 000000000..ca94fa649
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vclock_gettime.c
@@ -0,0 +1,339 @@
+/*
+ * Copyright 2006 Andi Kleen, SUSE Labs.
+ * Subject to the GNU Public License, v.2
+ *
+ * Fast user context implementation of clock_gettime, gettimeofday, and time.
+ *
+ * 32 Bit compat layer by Stefani Seibold <stefani@seibold.net>
+ *  sponsored by Rohde & Schwarz GmbH & Co. KG Munich/Germany
+ *
+ * The code should have no internal unresolved relocations.
+ * Check with readelf after changing.
+ */
+
+#include <uapi/linux/time.h>
+#include <asm/vgtod.h>
+#include <asm/hpet.h>
+#include <asm/vvar.h>
+#include <asm/unistd.h>
+#include <asm/msr.h>
+#include <linux/math64.h>
+#include <linux/time.h>
+
+#define gtod (&VVAR(vsyscall_gtod_data))
+
+extern int __vdso_clock_gettime(clockid_t clock, struct timespec *ts);
+extern int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz);
+extern time_t __vdso_time(time_t *t);
+
+#ifdef CONFIG_HPET_TIMER
+extern u8 hpet_page
+	__attribute__((visibility("hidden")));
+
+static notrace cycle_t vread_hpet(void)
+{
+	return *(const volatile u32 *)(&hpet_page + HPET_COUNTER);
+}
+#endif
+
+#ifndef BUILD_VDSO32
+
+#include <linux/kernel.h>
+#include <asm/vsyscall.h>
+#include <asm/fixmap.h>
+#include <asm/pvclock.h>
+
+notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
+{
+	long ret;
+	asm("syscall" : "=a" (ret) :
+	    "0" (__NR_clock_gettime), "D" (clock), "S" (ts) : "memory");
+	return ret;
+}
+
+notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
+{
+	long ret;
+
+	asm("syscall" : "=a" (ret) :
+	    "0" (__NR_gettimeofday), "D" (tv), "S" (tz) : "memory");
+	return ret;
+}
+
+#ifdef CONFIG_PARAVIRT_CLOCK
+
+static notrace const struct pvclock_vsyscall_time_info *get_pvti(int cpu)
+{
+	const struct pvclock_vsyscall_time_info *pvti_base;
+	int idx = cpu / (PAGE_SIZE/PVTI_SIZE);
+	int offset = cpu % (PAGE_SIZE/PVTI_SIZE);
+
+	BUG_ON(PVCLOCK_FIXMAP_BEGIN + idx > PVCLOCK_FIXMAP_END);
+
+	pvti_base = (struct pvclock_vsyscall_time_info *)
+		    __fix_to_virt(PVCLOCK_FIXMAP_BEGIN+idx);
+
+	return &pvti_base[offset];
+}
+
+static notrace cycle_t vread_pvclock(int *mode)
+{
+	const struct pvclock_vsyscall_time_info *pvti;
+	cycle_t ret;
+	u64 last;
+	u32 version;
+	u8 flags;
+	unsigned cpu, cpu1;
+
+
+	/*
+	 * Note: hypervisor must guarantee that:
+	 * 1. cpu ID number maps 1:1 to per-CPU pvclock time info.
+	 * 2. that per-CPU pvclock time info is updated if the
+	 *    underlying CPU changes.
+	 * 3. that version is increased whenever underlying CPU
+	 *    changes.
+	 *
+	 */
+	do {
+		cpu = __getcpu() & VGETCPU_CPU_MASK;
+		/* TODO: We can put vcpu id into higher bits of pvti.version.
+		 * This will save a couple of cycles by getting rid of
+		 * __getcpu() calls (Gleb).
+		 */
+
+		pvti = get_pvti(cpu);
+
+		version = __pvclock_read_cycles(&pvti->pvti, &ret, &flags);
+
+		/*
+		 * Test we're still on the cpu as well as the version.
+		 * We could have been migrated just after the first
+		 * vgetcpu but before fetching the version, so we
+		 * wouldn't notice a version change.
+		 */
+		cpu1 = __getcpu() & VGETCPU_CPU_MASK;
+	} while (unlikely(cpu != cpu1 ||
+			  (pvti->pvti.version & 1) ||
+			  pvti->pvti.version != version));
+
+	if (unlikely(!(flags & PVCLOCK_TSC_STABLE_BIT)))
+		*mode = VCLOCK_NONE;
+
+	/* refer to tsc.c read_tsc() comment for rationale */
+	last = gtod->cycle_last;
+
+	if (likely(ret >= last))
+		return ret;
+
+	return last;
+}
+#endif
+
+#else
+
+notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
+{
+	long ret;
+
+	asm(
+		"mov %%ebx, %%edx \n"
+		"mov %2, %%ebx \n"
+		"call __kernel_vsyscall \n"
+		"mov %%edx, %%ebx \n"
+		: "=a" (ret)
+		: "0" (__NR_clock_gettime), "g" (clock), "c" (ts)
+		: "memory", "edx");
+	return ret;
+}
+
+notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
+{
+	long ret;
+
+	asm(
+		"mov %%ebx, %%edx \n"
+		"mov %2, %%ebx \n"
+		"call __kernel_vsyscall \n"
+		"mov %%edx, %%ebx \n"
+		: "=a" (ret)
+		: "0" (__NR_gettimeofday), "g" (tv), "c" (tz)
+		: "memory", "edx");
+	return ret;
+}
+
+#ifdef CONFIG_PARAVIRT_CLOCK
+
+static notrace cycle_t vread_pvclock(int *mode)
+{
+	*mode = VCLOCK_NONE;
+	return 0;
+}
+#endif
+
+#endif
+
+notrace static cycle_t vread_tsc(void)
+{
+	cycle_t ret = (cycle_t)rdtsc_ordered();
+	u64 last = gtod->cycle_last;
+
+	if (likely(ret >= last))
+		return ret;
+
+	/*
+	 * GCC likes to generate cmov here, but this branch is extremely
+	 * predictable (it's just a funciton of time and the likely is
+	 * very likely) and there's a data dependence, so force GCC
+	 * to generate a branch instead.  I don't barrier() because
+	 * we don't actually need a barrier, and if this function
+	 * ever gets inlined it will generate worse code.
+	 */
+	asm volatile ("");
+	return last;
+}
+
+notrace static inline u64 vgetsns(int *mode)
+{
+	u64 v;
+	cycles_t cycles;
+
+	if (gtod->vclock_mode == VCLOCK_TSC)
+		cycles = vread_tsc();
+#ifdef CONFIG_HPET_TIMER
+	else if (gtod->vclock_mode == VCLOCK_HPET)
+		cycles = vread_hpet();
+#endif
+#ifdef CONFIG_PARAVIRT_CLOCK
+	else if (gtod->vclock_mode == VCLOCK_PVCLOCK)
+		cycles = vread_pvclock(mode);
+#endif
+	else
+		return 0;
+	v = (cycles - gtod->cycle_last) & gtod->mask;
+	return v * gtod->mult;
+}
+
+/* Code size doesn't matter (vdso is 4k anyway) and this is faster. */
+notrace static int __always_inline do_realtime(struct timespec *ts)
+{
+	unsigned long seq;
+	u64 ns;
+	int mode;
+
+	do {
+		seq = gtod_read_begin(gtod);
+		mode = gtod->vclock_mode;
+		ts->tv_sec = gtod->wall_time_sec;
+		ns = gtod->wall_time_snsec;
+		ns += vgetsns(&mode);
+		ns >>= gtod->shift;
+	} while (unlikely(gtod_read_retry(gtod, seq)));
+
+	ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
+	ts->tv_nsec = ns;
+
+	return mode;
+}
+
+notrace static int __always_inline do_monotonic(struct timespec *ts)
+{
+	unsigned long seq;
+	u64 ns;
+	int mode;
+
+	do {
+		seq = gtod_read_begin(gtod);
+		mode = gtod->vclock_mode;
+		ts->tv_sec = gtod->monotonic_time_sec;
+		ns = gtod->monotonic_time_snsec;
+		ns += vgetsns(&mode);
+		ns >>= gtod->shift;
+	} while (unlikely(gtod_read_retry(gtod, seq)));
+
+	ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
+	ts->tv_nsec = ns;
+
+	return mode;
+}
+
+notrace static void do_realtime_coarse(struct timespec *ts)
+{
+	unsigned long seq;
+	do {
+		seq = gtod_read_begin(gtod);
+		ts->tv_sec = gtod->wall_time_coarse_sec;
+		ts->tv_nsec = gtod->wall_time_coarse_nsec;
+	} while (unlikely(gtod_read_retry(gtod, seq)));
+}
+
+notrace static void do_monotonic_coarse(struct timespec *ts)
+{
+	unsigned long seq;
+	do {
+		seq = gtod_read_begin(gtod);
+		ts->tv_sec = gtod->monotonic_time_coarse_sec;
+		ts->tv_nsec = gtod->monotonic_time_coarse_nsec;
+	} while (unlikely(gtod_read_retry(gtod, seq)));
+}
+
+notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
+{
+	switch (clock) {
+	case CLOCK_REALTIME:
+		if (do_realtime(ts) == VCLOCK_NONE)
+			goto fallback;
+		break;
+	case CLOCK_MONOTONIC:
+		if (do_monotonic(ts) == VCLOCK_NONE)
+			goto fallback;
+		break;
+	case CLOCK_REALTIME_COARSE:
+		do_realtime_coarse(ts);
+		break;
+	case CLOCK_MONOTONIC_COARSE:
+		do_monotonic_coarse(ts);
+		break;
+	default:
+		goto fallback;
+	}
+
+	return 0;
+fallback:
+	return vdso_fallback_gettime(clock, ts);
+}
+int clock_gettime(clockid_t, struct timespec *)
+	__attribute__((weak, alias("__vdso_clock_gettime")));
+
+notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
+{
+	if (likely(tv != NULL)) {
+		if (unlikely(do_realtime((struct timespec *)tv) == VCLOCK_NONE))
+			return vdso_fallback_gtod(tv, tz);
+		tv->tv_usec /= 1000;
+	}
+	if (unlikely(tz != NULL)) {
+		tz->tz_minuteswest = gtod->tz_minuteswest;
+		tz->tz_dsttime = gtod->tz_dsttime;
+	}
+
+	return 0;
+}
+int gettimeofday(struct timeval *, struct timezone *)
+	__attribute__((weak, alias("__vdso_gettimeofday")));
+
+/*
+ * This will break when the xtime seconds get inaccurate, but that is
+ * unlikely
+ */
+notrace time_t __vdso_time(time_t *t)
+{
+	/* This is atomic on x86 so we don't need any locks. */
+	time_t result = ACCESS_ONCE(gtod->wall_time_sec);
+
+	if (t)
+		*t = result;
+	return result;
+}
+int time(time_t *t)
+	__attribute__((weak, alias("__vdso_time")));
diff --git a/kernel/arch/x86/entry/vdso/vdso-layout.lds.S b/kernel/arch/x86/entry/vdso/vdso-layout.lds.S
new file mode 100644
index 000000000..de2c92102
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso-layout.lds.S
@@ -0,0 +1,118 @@
+#include <asm/vdso.h>
+
+/*
+ * Linker script for vDSO.  This is an ELF shared object prelinked to
+ * its virtual address, and with only one read-only segment.
+ * This script controls its layout.
+ */
+
+#if defined(BUILD_VDSO64)
+# define SHDR_SIZE 64
+#elif defined(BUILD_VDSO32) || defined(BUILD_VDSOX32)
+# define SHDR_SIZE 40
+#else
+# error unknown VDSO target
+#endif
+
+#define NUM_FAKE_SHDRS 13
+
+SECTIONS
+{
+	/*
+	 * User/kernel shared data is before the vDSO.  This may be a little
+	 * uglier than putting it after the vDSO, but it avoids issues with
+	 * non-allocatable things that dangle past the end of the PT_LOAD
+	 * segment.
+	 */
+
+	vvar_start = . - 2 * PAGE_SIZE;
+	vvar_page = vvar_start;
+
+	/* Place all vvars at the offsets in asm/vvar.h. */
+#define EMIT_VVAR(name, offset) vvar_ ## name = vvar_page + offset;
+#define __VVAR_KERNEL_LDS
+#include <asm/vvar.h>
+#undef __VVAR_KERNEL_LDS
+#undef EMIT_VVAR
+
+	hpet_page = vvar_start + PAGE_SIZE;
+
+	. = SIZEOF_HEADERS;
+
+	.hash		: { *(.hash) }			:text
+	.gnu.hash	: { *(.gnu.hash) }
+	.dynsym		: { *(.dynsym) }
+	.dynstr		: { *(.dynstr) }
+	.gnu.version	: { *(.gnu.version) }
+	.gnu.version_d	: { *(.gnu.version_d) }
+	.gnu.version_r	: { *(.gnu.version_r) }
+
+	.dynamic	: { *(.dynamic) }		:text	:dynamic
+
+	.rodata		: {
+		*(.rodata*)
+		*(.data*)
+		*(.sdata*)
+		*(.got.plt) *(.got)
+		*(.gnu.linkonce.d.*)
+		*(.bss*)
+		*(.dynbss*)
+		*(.gnu.linkonce.b.*)
+
+		/*
+		 * Ideally this would live in a C file, but that won't
+		 * work cleanly for x32 until we start building the x32
+		 * C code using an x32 toolchain.
+		 */
+		VDSO_FAKE_SECTION_TABLE_START = .;
+		. = . + NUM_FAKE_SHDRS * SHDR_SIZE;
+		VDSO_FAKE_SECTION_TABLE_END = .;
+	}						:text
+
+	.fake_shstrtab	: { *(.fake_shstrtab) }		:text
+
+
+	.note		: { *(.note.*) }		:text	:note
+
+	.eh_frame_hdr	: { *(.eh_frame_hdr) }		:text	:eh_frame_hdr
+	.eh_frame	: { KEEP (*(.eh_frame)) }	:text
+
+
+	/*
+	 * Text is well-separated from actual data: there's plenty of
+	 * stuff that isn't used at runtime in between.
+	 */
+
+	.text		: { *(.text*) }			:text	=0x90909090,
+
+	/*
+	 * At the end so that eu-elflint stays happy when vdso2c strips
+	 * these.  A better implementation would avoid allocating space
+	 * for these.
+	 */
+	.altinstructions	: { *(.altinstructions) }	:text
+	.altinstr_replacement	: { *(.altinstr_replacement) }	:text
+
+	/DISCARD/ : {
+		*(.discard)
+		*(.discard.*)
+		*(__bug_table)
+	}
+}
+
+/*
+ * Very old versions of ld do not recognize this name token; use the constant.
+ */
+#define PT_GNU_EH_FRAME	0x6474e550
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+	text		PT_LOAD		FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
+	dynamic		PT_DYNAMIC	FLAGS(4);		/* PF_R */
+	note		PT_NOTE		FLAGS(4);		/* PF_R */
+	eh_frame_hdr	PT_GNU_EH_FRAME;
+}
diff --git a/kernel/arch/x86/entry/vdso/vdso-note.S b/kernel/arch/x86/entry/vdso/vdso-note.S
new file mode 100644
index 000000000..79a071e43
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso-note.S
@@ -0,0 +1,12 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+#include <linux/elfnote.h>
+
+ELFNOTE_START(Linux, 0, "a")
+	.long LINUX_VERSION_CODE
+ELFNOTE_END
diff --git a/kernel/arch/x86/entry/vdso/vdso.lds.S b/kernel/arch/x86/entry/vdso/vdso.lds.S
new file mode 100644
index 000000000..680793264
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso.lds.S
@@ -0,0 +1,29 @@
+/*
+ * Linker script for 64-bit vDSO.
+ * We #include the file to define the layout details.
+ *
+ * This file defines the version script giving the user-exported symbols in
+ * the DSO.
+ */
+
+#define BUILD_VDSO64
+
+#include "vdso-layout.lds.S"
+
+/*
+ * This controls what userland symbols we export from the vDSO.
+ */
+VERSION {
+	LINUX_2.6 {
+	global:
+		clock_gettime;
+		__vdso_clock_gettime;
+		gettimeofday;
+		__vdso_gettimeofday;
+		getcpu;
+		__vdso_getcpu;
+		time;
+		__vdso_time;
+	local: *;
+	};
+}
diff --git a/kernel/arch/x86/entry/vdso/vdso2c.c b/kernel/arch/x86/entry/vdso/vdso2c.c
new file mode 100644
index 000000000..785d9922b
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso2c.c
@@ -0,0 +1,253 @@
+/*
+ * vdso2c - A vdso image preparation tool
+ * Copyright (c) 2014 Andy Lutomirski and others
+ * Licensed under the GPL v2
+ *
+ * vdso2c requires stripped and unstripped input.  It would be trivial
+ * to fully strip the input in here, but, for reasons described below,
+ * we need to write a section table.  Doing this is more or less
+ * equivalent to dropping all non-allocatable sections, but it's
+ * easier to let objcopy handle that instead of doing it ourselves.
+ * If we ever need to do something fancier than what objcopy provides,
+ * it would be straightforward to add here.
+ *
+ * We're keep a section table for a few reasons:
+ *
+ * The Go runtime had a couple of bugs: it would read the section
+ * table to try to figure out how many dynamic symbols there were (it
+ * shouldn't have looked at the section table at all) and, if there
+ * were no SHT_SYNDYM section table entry, it would use an
+ * uninitialized value for the number of symbols.  An empty DYNSYM
+ * table would work, but I see no reason not to write a valid one (and
+ * keep full performance for old Go programs).  This hack is only
+ * needed on x86_64.
+ *
+ * The bug was introduced on 2012-08-31 by:
+ * https://code.google.com/p/go/source/detail?r=56ea40aac72b
+ * and was fixed on 2014-06-13 by:
+ * https://code.google.com/p/go/source/detail?r=fc1cd5e12595
+ *
+ * Binutils has issues debugging the vDSO: it reads the section table to
+ * find SHT_NOTE; it won't look at PT_NOTE for the in-memory vDSO, which
+ * would break build-id if we removed the section table.  Binutils
+ * also requires that shstrndx != 0.  See:
+ * https://sourceware.org/bugzilla/show_bug.cgi?id=17064
+ *
+ * elfutils might not look for PT_NOTE if there is a section table at
+ * all.  I don't know whether this matters for any practical purpose.
+ *
+ * For simplicity, rather than hacking up a partial section table, we
+ * just write a mostly complete one.  We omit non-dynamic symbols,
+ * though, since they're rather large.
+ *
+ * Once binutils gets fixed, we might be able to drop this for all but
+ * the 64-bit vdso, since build-id only works in kernel RPMs, and
+ * systems that update to new enough kernel RPMs will likely update
+ * binutils in sync.  build-id has never worked for home-built kernel
+ * RPMs without manual symlinking, and I suspect that no one ever does
+ * that.
+ */
+
+#include <inttypes.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <err.h>
+
+#include <sys/mman.h>
+#include <sys/types.h>
+
+#include <tools/le_byteshift.h>
+
+#include <linux/elf.h>
+#include <linux/types.h>
+
+const char *outfilename;
+
+/* Symbols that we need in vdso2c. */
+enum {
+	sym_vvar_start,
+	sym_vvar_page,
+	sym_hpet_page,
+	sym_VDSO_FAKE_SECTION_TABLE_START,
+	sym_VDSO_FAKE_SECTION_TABLE_END,
+};
+
+const int special_pages[] = {
+	sym_vvar_page,
+	sym_hpet_page,
+};
+
+struct vdso_sym {
+	const char *name;
+	bool export;
+};
+
+struct vdso_sym required_syms[] = {
+	[sym_vvar_start] = {"vvar_start", true},
+	[sym_vvar_page] = {"vvar_page", true},
+	[sym_hpet_page] = {"hpet_page", true},
+	[sym_VDSO_FAKE_SECTION_TABLE_START] = {
+		"VDSO_FAKE_SECTION_TABLE_START", false
+	},
+	[sym_VDSO_FAKE_SECTION_TABLE_END] = {
+		"VDSO_FAKE_SECTION_TABLE_END", false
+	},
+	{"VDSO32_NOTE_MASK", true},
+	{"__kernel_vsyscall", true},
+	{"__kernel_sigreturn", true},
+	{"__kernel_rt_sigreturn", true},
+	{"int80_landing_pad", true},
+};
+
+__attribute__((format(printf, 1, 2))) __attribute__((noreturn))
+static void fail(const char *format, ...)
+{
+	va_list ap;
+	va_start(ap, format);
+	fprintf(stderr, "Error: ");
+	vfprintf(stderr, format, ap);
+	if (outfilename)
+		unlink(outfilename);
+	exit(1);
+	va_end(ap);
+}
+
+/*
+ * Evil macros for little-endian reads and writes
+ */
+#define GLE(x, bits, ifnot)						\
+	__builtin_choose_expr(						\
+		(sizeof(*(x)) == bits/8),				\
+		(__typeof__(*(x)))get_unaligned_le##bits(x), ifnot)
+
+extern void bad_get_le(void);
+#define LAST_GLE(x)							\
+	__builtin_choose_expr(sizeof(*(x)) == 1, *(x), bad_get_le())
+
+#define GET_LE(x)							\
+	GLE(x, 64, GLE(x, 32, GLE(x, 16, LAST_GLE(x))))
+
+#define PLE(x, val, bits, ifnot)					\
+	__builtin_choose_expr(						\
+		(sizeof(*(x)) == bits/8),				\
+		put_unaligned_le##bits((val), (x)), ifnot)
+
+extern void bad_put_le(void);
+#define LAST_PLE(x, val)						\
+	__builtin_choose_expr(sizeof(*(x)) == 1, *(x) = (val), bad_put_le())
+
+#define PUT_LE(x, val)					\
+	PLE(x, val, 64, PLE(x, val, 32, PLE(x, val, 16, LAST_PLE(x, val))))
+
+
+#define NSYMS (sizeof(required_syms) / sizeof(required_syms[0]))
+
+#define BITSFUNC3(name, bits, suffix) name##bits##suffix
+#define BITSFUNC2(name, bits, suffix) BITSFUNC3(name, bits, suffix)
+#define BITSFUNC(name) BITSFUNC2(name, ELF_BITS, )
+
+#define INT_BITS BITSFUNC2(int, ELF_BITS, _t)
+
+#define ELF_BITS_XFORM2(bits, x) Elf##bits##_##x
+#define ELF_BITS_XFORM(bits, x) ELF_BITS_XFORM2(bits, x)
+#define ELF(x) ELF_BITS_XFORM(ELF_BITS, x)
+
+#define ELF_BITS 64
+#include "vdso2c.h"
+#undef ELF_BITS
+
+#define ELF_BITS 32
+#include "vdso2c.h"
+#undef ELF_BITS
+
+static void go(void *raw_addr, size_t raw_len,
+	       void *stripped_addr, size_t stripped_len,
+	       FILE *outfile, const char *name)
+{
+	Elf64_Ehdr *hdr = (Elf64_Ehdr *)raw_addr;
+
+	if (hdr->e_ident[EI_CLASS] == ELFCLASS64) {
+		go64(raw_addr, raw_len, stripped_addr, stripped_len,
+		     outfile, name);
+	} else if (hdr->e_ident[EI_CLASS] == ELFCLASS32) {
+		go32(raw_addr, raw_len, stripped_addr, stripped_len,
+		     outfile, name);
+	} else {
+		fail("unknown ELF class\n");
+	}
+}
+
+static void map_input(const char *name, void **addr, size_t *len, int prot)
+{
+	off_t tmp_len;
+
+	int fd = open(name, O_RDONLY);
+	if (fd == -1)
+		err(1, "%s", name);
+
+	tmp_len = lseek(fd, 0, SEEK_END);
+	if (tmp_len == (off_t)-1)
+		err(1, "lseek");
+	*len = (size_t)tmp_len;
+
+	*addr = mmap(NULL, tmp_len, prot, MAP_PRIVATE, fd, 0);
+	if (*addr == MAP_FAILED)
+		err(1, "mmap");
+
+	close(fd);
+}
+
+int main(int argc, char **argv)
+{
+	size_t raw_len, stripped_len;
+	void *raw_addr, *stripped_addr;
+	FILE *outfile;
+	char *name, *tmp;
+	int namelen;
+
+	if (argc != 4) {
+		printf("Usage: vdso2c RAW_INPUT STRIPPED_INPUT OUTPUT\n");
+		return 1;
+	}
+
+	/*
+	 * Figure out the struct name.  If we're writing to a .so file,
+	 * generate raw output insted.
+	 */
+	name = strdup(argv[3]);
+	namelen = strlen(name);
+	if (namelen >= 3 && !strcmp(name + namelen - 3, ".so")) {
+		name = NULL;
+	} else {
+		tmp = strrchr(name, '/');
+		if (tmp)
+			name = tmp + 1;
+		tmp = strchr(name, '.');
+		if (tmp)
+			*tmp = '\0';
+		for (tmp = name; *tmp; tmp++)
+			if (*tmp == '-')
+				*tmp = '_';
+	}
+
+	map_input(argv[1], &raw_addr, &raw_len, PROT_READ);
+	map_input(argv[2], &stripped_addr, &stripped_len, PROT_READ);
+
+	outfilename = argv[3];
+	outfile = fopen(outfilename, "w");
+	if (!outfile)
+		err(1, "%s", argv[2]);
+
+	go(raw_addr, raw_len, stripped_addr, stripped_len, outfile, name);
+
+	munmap(raw_addr, raw_len);
+	munmap(stripped_addr, stripped_len);
+	fclose(outfile);
+
+	return 0;
+}
diff --git a/kernel/arch/x86/entry/vdso/vdso2c.h b/kernel/arch/x86/entry/vdso/vdso2c.h
new file mode 100644
index 000000000..022498755
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso2c.h
@@ -0,0 +1,175 @@
+/*
+ * This file is included twice from vdso2c.c.  It generates code for 32-bit
+ * and 64-bit vDSOs.  We need both for 64-bit builds, since 32-bit vDSOs
+ * are built for 32-bit userspace.
+ */
+
+static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
+			 void *stripped_addr, size_t stripped_len,
+			 FILE *outfile, const char *name)
+{
+	int found_load = 0;
+	unsigned long load_size = -1;  /* Work around bogus warning */
+	unsigned long mapping_size;
+	ELF(Ehdr) *hdr = (ELF(Ehdr) *)raw_addr;
+	int i;
+	unsigned long j;
+	ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr,
+		*alt_sec = NULL;
+	ELF(Dyn) *dyn = 0, *dyn_end = 0;
+	const char *secstrings;
+	INT_BITS syms[NSYMS] = {};
+
+	ELF(Phdr) *pt = (ELF(Phdr) *)(raw_addr + GET_LE(&hdr->e_phoff));
+
+	/* Walk the segment table. */
+	for (i = 0; i < GET_LE(&hdr->e_phnum); i++) {
+		if (GET_LE(&pt[i].p_type) == PT_LOAD) {
+			if (found_load)
+				fail("multiple PT_LOAD segs\n");
+
+			if (GET_LE(&pt[i].p_offset) != 0 ||
+			    GET_LE(&pt[i].p_vaddr) != 0)
+				fail("PT_LOAD in wrong place\n");
+
+			if (GET_LE(&pt[i].p_memsz) != GET_LE(&pt[i].p_filesz))
+				fail("cannot handle memsz != filesz\n");
+
+			load_size = GET_LE(&pt[i].p_memsz);
+			found_load = 1;
+		} else if (GET_LE(&pt[i].p_type) == PT_DYNAMIC) {
+			dyn = raw_addr + GET_LE(&pt[i].p_offset);
+			dyn_end = raw_addr + GET_LE(&pt[i].p_offset) +
+				GET_LE(&pt[i].p_memsz);
+		}
+	}
+	if (!found_load)
+		fail("no PT_LOAD seg\n");
+
+	if (stripped_len < load_size)
+		fail("stripped input is too short\n");
+
+	/* Walk the dynamic table */
+	for (i = 0; dyn + i < dyn_end &&
+		     GET_LE(&dyn[i].d_tag) != DT_NULL; i++) {
+		typeof(dyn[i].d_tag) tag = GET_LE(&dyn[i].d_tag);
+		if (tag == DT_REL || tag == DT_RELSZ || tag == DT_RELA ||
+		    tag == DT_RELENT || tag == DT_TEXTREL)
+			fail("vdso image contains dynamic relocations\n");
+	}
+
+	/* Walk the section table */
+	secstrings_hdr = raw_addr + GET_LE(&hdr->e_shoff) +
+		GET_LE(&hdr->e_shentsize)*GET_LE(&hdr->e_shstrndx);
+	secstrings = raw_addr + GET_LE(&secstrings_hdr->sh_offset);
+	for (i = 0; i < GET_LE(&hdr->e_shnum); i++) {
+		ELF(Shdr) *sh = raw_addr + GET_LE(&hdr->e_shoff) +
+			GET_LE(&hdr->e_shentsize) * i;
+		if (GET_LE(&sh->sh_type) == SHT_SYMTAB)
+			symtab_hdr = sh;
+
+		if (!strcmp(secstrings + GET_LE(&sh->sh_name),
+			    ".altinstructions"))
+			alt_sec = sh;
+	}
+
+	if (!symtab_hdr)
+		fail("no symbol table\n");
+
+	strtab_hdr = raw_addr + GET_LE(&hdr->e_shoff) +
+		GET_LE(&hdr->e_shentsize) * GET_LE(&symtab_hdr->sh_link);
+
+	/* Walk the symbol table */
+	for (i = 0;
+	     i < GET_LE(&symtab_hdr->sh_size) / GET_LE(&symtab_hdr->sh_entsize);
+	     i++) {
+		int k;
+		ELF(Sym) *sym = raw_addr + GET_LE(&symtab_hdr->sh_offset) +
+			GET_LE(&symtab_hdr->sh_entsize) * i;
+		const char *name = raw_addr + GET_LE(&strtab_hdr->sh_offset) +
+			GET_LE(&sym->st_name);
+
+		for (k = 0; k < NSYMS; k++) {
+			if (!strcmp(name, required_syms[k].name)) {
+				if (syms[k]) {
+					fail("duplicate symbol %s\n",
+					     required_syms[k].name);
+				}
+
+				/*
+				 * Careful: we use negative addresses, but
+				 * st_value is unsigned, so we rely
+				 * on syms[k] being a signed type of the
+				 * correct width.
+				 */
+				syms[k] = GET_LE(&sym->st_value);
+			}
+		}
+	}
+
+	/* Validate mapping addresses. */
+	for (i = 0; i < sizeof(special_pages) / sizeof(special_pages[0]); i++) {
+		INT_BITS symval = syms[special_pages[i]];
+
+		if (!symval)
+			continue;  /* The mapping isn't used; ignore it. */
+
+		if (symval % 4096)
+			fail("%s must be a multiple of 4096\n",
+			     required_syms[i].name);
+		if (symval + 4096 < syms[sym_vvar_start])
+			fail("%s underruns vvar_start\n",
+			     required_syms[i].name);
+		if (symval + 4096 > 0)
+			fail("%s is on the wrong side of the vdso text\n",
+			     required_syms[i].name);
+	}
+	if (syms[sym_vvar_start] % 4096)
+		fail("vvar_begin must be a multiple of 4096\n");
+
+	if (!name) {
+		fwrite(stripped_addr, stripped_len, 1, outfile);
+		return;
+	}
+
+	mapping_size = (stripped_len + 4095) / 4096 * 4096;
+
+	fprintf(outfile, "/* AUTOMATICALLY GENERATED -- DO NOT EDIT */\n\n");
+	fprintf(outfile, "#include <linux/linkage.h>\n");
+	fprintf(outfile, "#include <asm/page_types.h>\n");
+	fprintf(outfile, "#include <asm/vdso.h>\n");
+	fprintf(outfile, "\n");
+	fprintf(outfile,
+		"static unsigned char raw_data[%lu] __page_aligned_data = {",
+		mapping_size);
+	for (j = 0; j < stripped_len; j++) {
+		if (j % 10 == 0)
+			fprintf(outfile, "\n\t");
+		fprintf(outfile, "0x%02X, ",
+			(int)((unsigned char *)stripped_addr)[j]);
+	}
+	fprintf(outfile, "\n};\n\n");
+
+	fprintf(outfile, "static struct page *pages[%lu];\n\n",
+		mapping_size / 4096);
+
+	fprintf(outfile, "const struct vdso_image %s = {\n", name);
+	fprintf(outfile, "\t.data = raw_data,\n");
+	fprintf(outfile, "\t.size = %lu,\n", mapping_size);
+	fprintf(outfile, "\t.text_mapping = {\n");
+	fprintf(outfile, "\t\t.name = \"[vdso]\",\n");
+	fprintf(outfile, "\t\t.pages = pages,\n");
+	fprintf(outfile, "\t},\n");
+	if (alt_sec) {
+		fprintf(outfile, "\t.alt = %lu,\n",
+			(unsigned long)GET_LE(&alt_sec->sh_offset));
+		fprintf(outfile, "\t.alt_len = %lu,\n",
+			(unsigned long)GET_LE(&alt_sec->sh_size));
+	}
+	for (i = 0; i < NSYMS; i++) {
+		if (required_syms[i].export && syms[i])
+			fprintf(outfile, "\t.sym_%s = %" PRIi64 ",\n",
+				required_syms[i].name, (int64_t)syms[i]);
+	}
+	fprintf(outfile, "};\n");
+}
diff --git a/kernel/arch/x86/entry/vdso/vdso32-setup.c b/kernel/arch/x86/entry/vdso/vdso32-setup.c
new file mode 100644
index 000000000..08a317a9a
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso32-setup.c
@@ -0,0 +1,94 @@
+/*
+ * (C) Copyright 2002 Linus Torvalds
+ * Portions based on the vdso-randomization code from exec-shield:
+ * Copyright(C) 2005-2006, Red Hat, Inc., Ingo Molnar
+ *
+ * This file contains the needed initializations to support sysenter.
+ */
+
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/kernel.h>
+#include <linux/mm_types.h>
+
+#include <asm/cpufeature.h>
+#include <asm/processor.h>
+#include <asm/vdso.h>
+
+#ifdef CONFIG_COMPAT_VDSO
+#define VDSO_DEFAULT	0
+#else
+#define VDSO_DEFAULT	1
+#endif
+
+/*
+ * Should the kernel map a VDSO page into processes and pass its
+ * address down to glibc upon exec()?
+ */
+unsigned int __read_mostly vdso32_enabled = VDSO_DEFAULT;
+
+static int __init vdso32_setup(char *s)
+{
+	vdso32_enabled = simple_strtoul(s, NULL, 0);
+
+	if (vdso32_enabled > 1)
+		pr_warn("vdso32 values other than 0 and 1 are no longer allowed; vdso disabled\n");
+
+	return 1;
+}
+
+/*
+ * For consistency, the argument vdso32=[012] affects the 32-bit vDSO
+ * behavior on both 64-bit and 32-bit kernels.
+ * On 32-bit kernels, vdso=[012] means the same thing.
+ */
+__setup("vdso32=", vdso32_setup);
+
+#ifdef CONFIG_X86_32
+__setup_param("vdso=", vdso_setup, vdso32_setup, 0);
+#endif
+
+int __init sysenter_setup(void)
+{
+	init_vdso_image(&vdso_image_32);
+
+	return 0;
+}
+
+#ifdef CONFIG_X86_64
+
+subsys_initcall(sysenter_setup);
+
+#ifdef CONFIG_SYSCTL
+/* Register vsyscall32 into the ABI table */
+#include <linux/sysctl.h>
+
+static struct ctl_table abi_table2[] = {
+	{
+		.procname	= "vsyscall32",
+		.data		= &vdso32_enabled,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{}
+};
+
+static struct ctl_table abi_root_table2[] = {
+	{
+		.procname = "abi",
+		.mode = 0555,
+		.child = abi_table2
+	},
+	{}
+};
+
+static __init int ia32_binfmt_init(void)
+{
+	register_sysctl_table(abi_root_table2);
+	return 0;
+}
+__initcall(ia32_binfmt_init);
+#endif /* CONFIG_SYSCTL */
+
+#endif	/* CONFIG_X86_64 */
diff --git a/kernel/arch/x86/entry/vdso/vdso32/.gitignore b/kernel/arch/x86/entry/vdso/vdso32/.gitignore
new file mode 100644
index 000000000..e45fba9d0
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso32/.gitignore
@@ -0,0 +1 @@
+vdso32.lds
diff --git a/kernel/arch/x86/entry/vdso/vdso32/note.S b/kernel/arch/x86/entry/vdso/vdso32/note.S
new file mode 100644
index 000000000..c83f25734
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso32/note.S
@@ -0,0 +1,44 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/version.h>
+#include <linux/elfnote.h>
+
+/* Ideally this would use UTS_NAME, but using a quoted string here
+   doesn't work. Remember to change this when changing the
+   kernel's name. */
+ELFNOTE_START(Linux, 0, "a")
+	.long LINUX_VERSION_CODE
+ELFNOTE_END
+
+#ifdef CONFIG_XEN
+/*
+ * Add a special note telling glibc's dynamic linker a fake hardware
+ * flavor that it will use to choose the search path for libraries in the
+ * same way it uses real hardware capabilities like "mmx".
+ * We supply "nosegneg" as the fake capability, to indicate that we
+ * do not like negative offsets in instructions using segment overrides,
+ * since we implement those inefficiently.  This makes it possible to
+ * install libraries optimized to avoid those access patterns in someplace
+ * like /lib/i686/tls/nosegneg.  Note that an /etc/ld.so.conf.d/file
+ * corresponding to the bits here is needed to make ldconfig work right.
+ * It should contain:
+ *	hwcap 1 nosegneg
+ * to match the mapping of bit to name that we give here.
+ *
+ * At runtime, the fake hardware feature will be considered to be present
+ * if its bit is set in the mask word.  So, we start with the mask 0, and
+ * at boot time we set VDSO_NOTE_NONEGSEG_BIT if running under Xen.
+ */
+
+#include "../../xen/vdso.h"	/* Defines VDSO_NOTE_NONEGSEG_BIT.  */
+
+ELFNOTE_START(GNU, 2, "a")
+	.long 1			/* ncaps */
+VDSO32_NOTE_MASK:		/* Symbol used by arch/x86/xen/setup.c */
+	.long 0			/* mask */
+	.byte VDSO_NOTE_NONEGSEG_BIT; .asciz "nosegneg"	/* bit, name */
+ELFNOTE_END
+#endif
diff --git a/kernel/arch/x86/entry/vdso/vdso32/sigreturn.S b/kernel/arch/x86/entry/vdso/vdso32/sigreturn.S
new file mode 100644
index 000000000..d7ec4e251
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso32/sigreturn.S
@@ -0,0 +1,145 @@
+/*
+ * Common code for the sigreturn entry points in vDSO images.
+ * So far this code is the same for both int80 and sysenter versions.
+ * This file is #include'd by int80.S et al to define them first thing.
+ * The kernel assumes that the addresses of these routines are constant
+ * for all vDSO implementations.
+ */
+
+#include <linux/linkage.h>
+#include <asm/unistd_32.h>
+#include <asm/asm-offsets.h>
+
+#ifndef SYSCALL_ENTER_KERNEL
+#define	SYSCALL_ENTER_KERNEL	int $0x80
+#endif
+
+	.text
+	.globl __kernel_sigreturn
+	.type __kernel_sigreturn,@function
+	nop /* this guy is needed for .LSTARTFDEDLSI1 below (watch for HACK) */
+	ALIGN
+__kernel_sigreturn:
+.LSTART_sigreturn:
+	popl %eax		/* XXX does this mean it needs unwind info? */
+	movl $__NR_sigreturn, %eax
+	SYSCALL_ENTER_KERNEL
+.LEND_sigreturn:
+	nop
+	.size __kernel_sigreturn,.-.LSTART_sigreturn
+
+	.globl __kernel_rt_sigreturn
+	.type __kernel_rt_sigreturn,@function
+	ALIGN
+__kernel_rt_sigreturn:
+.LSTART_rt_sigreturn:
+	movl $__NR_rt_sigreturn, %eax
+	SYSCALL_ENTER_KERNEL
+.LEND_rt_sigreturn:
+	nop
+	.size __kernel_rt_sigreturn,.-.LSTART_rt_sigreturn
+	.previous
+
+	.section .eh_frame,"a",@progbits
+.LSTARTFRAMEDLSI1:
+	.long .LENDCIEDLSI1-.LSTARTCIEDLSI1
+.LSTARTCIEDLSI1:
+	.long 0			/* CIE ID */
+	.byte 1			/* Version number */
+	.string "zRS"		/* NUL-terminated augmentation string */
+	.uleb128 1		/* Code alignment factor */
+	.sleb128 -4		/* Data alignment factor */
+	.byte 8			/* Return address register column */
+	.uleb128 1		/* Augmentation value length */
+	.byte 0x1b		/* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */
+	.byte 0			/* DW_CFA_nop */
+	.align 4
+.LENDCIEDLSI1:
+	.long .LENDFDEDLSI1-.LSTARTFDEDLSI1 /* Length FDE */
+.LSTARTFDEDLSI1:
+	.long .LSTARTFDEDLSI1-.LSTARTFRAMEDLSI1 /* CIE pointer */
+	/* HACK: The dwarf2 unwind routines will subtract 1 from the
+	   return address to get an address in the middle of the
+	   presumed call instruction.  Since we didn't get here via
+	   a call, we need to include the nop before the real start
+	   to make up for it.  */
+	.long .LSTART_sigreturn-1-.	/* PC-relative start address */
+	.long .LEND_sigreturn-.LSTART_sigreturn+1
+	.uleb128 0			/* Augmentation */
+	/* What follows are the instructions for the table generation.
+	   We record the locations of each register saved.  This is
+	   complicated by the fact that the "CFA" is always assumed to
+	   be the value of the stack pointer in the caller.  This means
+	   that we must define the CFA of this body of code to be the
+	   saved value of the stack pointer in the sigcontext.  Which
+	   also means that there is no fixed relation to the other
+	   saved registers, which means that we must use DW_CFA_expression
+	   to compute their addresses.  It also means that when we
+	   adjust the stack with the popl, we have to do it all over again.  */
+
+#define do_cfa_expr(offset)						\
+	.byte 0x0f;			/* DW_CFA_def_cfa_expression */	\
+	.uleb128 1f-0f;			/*   length */			\
+0:	.byte 0x74;			/*     DW_OP_breg4 */		\
+	.sleb128 offset;		/*      offset */		\
+	.byte 0x06;			/*     DW_OP_deref */		\
+1:
+
+#define do_expr(regno, offset)						\
+	.byte 0x10;			/* DW_CFA_expression */		\
+	.uleb128 regno;			/*   regno */			\
+	.uleb128 1f-0f;			/*   length */			\
+0:	.byte 0x74;			/*     DW_OP_breg4 */		\
+	.sleb128 offset;		/*       offset */		\
+1:
+
+	do_cfa_expr(IA32_SIGCONTEXT_sp+4)
+	do_expr(0, IA32_SIGCONTEXT_ax+4)
+	do_expr(1, IA32_SIGCONTEXT_cx+4)
+	do_expr(2, IA32_SIGCONTEXT_dx+4)
+	do_expr(3, IA32_SIGCONTEXT_bx+4)
+	do_expr(5, IA32_SIGCONTEXT_bp+4)
+	do_expr(6, IA32_SIGCONTEXT_si+4)
+	do_expr(7, IA32_SIGCONTEXT_di+4)
+	do_expr(8, IA32_SIGCONTEXT_ip+4)
+
+	.byte 0x42	/* DW_CFA_advance_loc 2 -- nop; popl eax. */
+
+	do_cfa_expr(IA32_SIGCONTEXT_sp)
+	do_expr(0, IA32_SIGCONTEXT_ax)
+	do_expr(1, IA32_SIGCONTEXT_cx)
+	do_expr(2, IA32_SIGCONTEXT_dx)
+	do_expr(3, IA32_SIGCONTEXT_bx)
+	do_expr(5, IA32_SIGCONTEXT_bp)
+	do_expr(6, IA32_SIGCONTEXT_si)
+	do_expr(7, IA32_SIGCONTEXT_di)
+	do_expr(8, IA32_SIGCONTEXT_ip)
+
+	.align 4
+.LENDFDEDLSI1:
+
+	.long .LENDFDEDLSI2-.LSTARTFDEDLSI2 /* Length FDE */
+.LSTARTFDEDLSI2:
+	.long .LSTARTFDEDLSI2-.LSTARTFRAMEDLSI1 /* CIE pointer */
+	/* HACK: See above wrt unwind library assumptions.  */
+	.long .LSTART_rt_sigreturn-1-.	/* PC-relative start address */
+	.long .LEND_rt_sigreturn-.LSTART_rt_sigreturn+1
+	.uleb128 0			/* Augmentation */
+	/* What follows are the instructions for the table generation.
+	   We record the locations of each register saved.  This is
+	   slightly less complicated than the above, since we don't
+	   modify the stack pointer in the process.  */
+
+	do_cfa_expr(IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_sp)
+	do_expr(0, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_ax)
+	do_expr(1, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_cx)
+	do_expr(2, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_dx)
+	do_expr(3, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_bx)
+	do_expr(5, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_bp)
+	do_expr(6, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_si)
+	do_expr(7, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_di)
+	do_expr(8, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_ip)
+
+	.align 4
+.LENDFDEDLSI2:
+	.previous
diff --git a/kernel/arch/x86/entry/vdso/vdso32/system_call.S b/kernel/arch/x86/entry/vdso/vdso32/system_call.S
new file mode 100644
index 000000000..3a1d92970
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso32/system_call.S
@@ -0,0 +1,89 @@
+/*
+ * AT_SYSINFO entry point
+*/
+
+#include <asm/dwarf2.h>
+#include <asm/cpufeature.h>
+#include <asm/alternative-asm.h>
+
+/*
+ * First get the common code for the sigreturn entry points.
+ * This must come first.
+ */
+#include "sigreturn.S"
+
+	.text
+	.globl __kernel_vsyscall
+	.type __kernel_vsyscall,@function
+	ALIGN
+__kernel_vsyscall:
+	CFI_STARTPROC
+	/*
+	 * Reshuffle regs so that all of any of the entry instructions
+	 * will preserve enough state.
+	 *
+	 * A really nice entry sequence would be:
+	 *  pushl %edx
+	 *  pushl %ecx
+	 *  movl  %esp, %ecx
+	 *
+	 * Unfortunately, naughty Android versions between July and December
+	 * 2015 actually hardcode the traditional Linux SYSENTER entry
+	 * sequence.  That is severely broken for a number of reasons (ask
+	 * anyone with an AMD CPU, for example).  Nonetheless, we try to keep
+	 * it working approximately as well as it ever worked.
+	 *
+	 * This link may eludicate some of the history:
+	 *   https://android-review.googlesource.com/#/q/Iac3295376d61ef83e713ac9b528f3b50aa780cd7
+	 * personally, I find it hard to understand what's going on there.
+	 *
+	 * Note to future user developers: DO NOT USE SYSENTER IN YOUR CODE.
+	 * Execute an indirect call to the address in the AT_SYSINFO auxv
+	 * entry.  That is the ONLY correct way to make a fast 32-bit system
+	 * call on Linux.  (Open-coding int $0x80 is also fine, but it's
+	 * slow.)
+	 */
+	pushl	%ecx
+	CFI_ADJUST_CFA_OFFSET	4
+	CFI_REL_OFFSET		ecx, 0
+	pushl	%edx
+	CFI_ADJUST_CFA_OFFSET	4
+	CFI_REL_OFFSET		edx, 0
+	pushl	%ebp
+	CFI_ADJUST_CFA_OFFSET	4
+	CFI_REL_OFFSET		ebp, 0
+
+	#define SYSENTER_SEQUENCE	"movl %esp, %ebp; sysenter"
+	#define SYSCALL_SEQUENCE	"movl %ecx, %ebp; syscall"
+
+#ifdef CONFIG_X86_64
+	/* If SYSENTER (Intel) or SYSCALL32 (AMD) is available, use it. */
+	ALTERNATIVE_2 "", SYSENTER_SEQUENCE, X86_FEATURE_SYSENTER32, \
+	                  SYSCALL_SEQUENCE,  X86_FEATURE_SYSCALL32
+#else
+	ALTERNATIVE "", SYSENTER_SEQUENCE, X86_FEATURE_SEP
+#endif
+
+	/* Enter using int $0x80 */
+	int	$0x80
+GLOBAL(int80_landing_pad)
+
+	/*
+	 * Restore EDX and ECX in case they were clobbered.  EBP is not
+	 * clobbered (the kernel restores it), but it's cleaner and
+	 * probably faster to pop it than to adjust ESP using addl.
+	 */
+	popl	%ebp
+	CFI_RESTORE		ebp
+	CFI_ADJUST_CFA_OFFSET	-4
+	popl	%edx
+	CFI_RESTORE		edx
+	CFI_ADJUST_CFA_OFFSET	-4
+	popl	%ecx
+	CFI_RESTORE		ecx
+	CFI_ADJUST_CFA_OFFSET	-4
+	ret
+	CFI_ENDPROC
+
+	.size __kernel_vsyscall,.-__kernel_vsyscall
+	.previous
diff --git a/kernel/arch/x86/entry/vdso/vdso32/vclock_gettime.c b/kernel/arch/x86/entry/vdso/vdso32/vclock_gettime.c
new file mode 100644
index 000000000..87a86e017
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso32/vclock_gettime.c
@@ -0,0 +1,32 @@
+#define BUILD_VDSO32
+
+#ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
+#undef CONFIG_OPTIMIZE_INLINING
+#endif
+
+#undef CONFIG_X86_PPRO_FENCE
+
+#ifdef CONFIG_X86_64
+
+/*
+ * in case of a 32 bit VDSO for a 64 bit kernel fake a 32 bit kernel
+ * configuration
+ */
+#undef CONFIG_64BIT
+#undef CONFIG_X86_64
+#undef CONFIG_PGTABLE_LEVELS
+#undef CONFIG_ILLEGAL_POINTER_VALUE
+#undef CONFIG_SPARSEMEM_VMEMMAP
+#undef CONFIG_NR_CPUS
+
+#define CONFIG_X86_32 1
+#define CONFIG_PGTABLE_LEVELS 2
+#define CONFIG_PAGE_OFFSET 0
+#define CONFIG_ILLEGAL_POINTER_VALUE 0
+#define CONFIG_NR_CPUS 1
+
+#define BUILD_VDSO32_64
+
+#endif
+
+#include "../vclock_gettime.c"
diff --git a/kernel/arch/x86/entry/vdso/vdso32/vdso-fakesections.c b/kernel/arch/x86/entry/vdso/vdso32/vdso-fakesections.c
new file mode 100644
index 000000000..541468e25
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso32/vdso-fakesections.c
@@ -0,0 +1 @@
+#include "../vdso-fakesections.c"
diff --git a/kernel/arch/x86/entry/vdso/vdso32/vdso32.lds.S b/kernel/arch/x86/entry/vdso/vdso32/vdso32.lds.S
new file mode 100644
index 000000000..31056cf29
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdso32/vdso32.lds.S
@@ -0,0 +1,37 @@
+/*
+ * Linker script for 32-bit vDSO.
+ * We #include the file to define the layout details.
+ *
+ * This file defines the version script giving the user-exported symbols in
+ * the DSO.
+ */
+
+#include <asm/page.h>
+
+#define BUILD_VDSO32
+
+#include "../vdso-layout.lds.S"
+
+/* The ELF entry point can be used to set the AT_SYSINFO value.  */
+ENTRY(__kernel_vsyscall);
+
+/*
+ * This controls what userland symbols we export from the vDSO.
+ */
+VERSION
+{
+	LINUX_2.6 {
+	global:
+		__vdso_clock_gettime;
+		__vdso_gettimeofday;
+		__vdso_time;
+	};
+
+	LINUX_2.5 {
+	global:
+		__kernel_vsyscall;
+		__kernel_sigreturn;
+		__kernel_rt_sigreturn;
+	local: *;
+	};
+}
diff --git a/kernel/arch/x86/entry/vdso/vdsox32.lds.S b/kernel/arch/x86/entry/vdso/vdsox32.lds.S
new file mode 100644
index 000000000..697c11ece
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vdsox32.lds.S
@@ -0,0 +1,25 @@
+/*
+ * Linker script for x32 vDSO.
+ * We #include the file to define the layout details.
+ *
+ * This file defines the version script giving the user-exported symbols in
+ * the DSO.
+ */
+
+#define BUILD_VDSOX32
+
+#include "vdso-layout.lds.S"
+
+/*
+ * This controls what userland symbols we export from the vDSO.
+ */
+VERSION {
+	LINUX_2.6 {
+	global:
+		__vdso_clock_gettime;
+		__vdso_gettimeofday;
+		__vdso_getcpu;
+		__vdso_time;
+	local: *;
+	};
+}
diff --git a/kernel/arch/x86/entry/vdso/vgetcpu.c b/kernel/arch/x86/entry/vdso/vgetcpu.c
new file mode 100644
index 000000000..8ec3d1f4c
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vgetcpu.c
@@ -0,0 +1,28 @@
+/*
+ * Copyright 2006 Andi Kleen, SUSE Labs.
+ * Subject to the GNU Public License, v.2
+ *
+ * Fast user context implementation of getcpu()
+ */
+
+#include <linux/kernel.h>
+#include <linux/getcpu.h>
+#include <linux/time.h>
+#include <asm/vgtod.h>
+
+notrace long
+__vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused)
+{
+	unsigned int p;
+
+	p = __getcpu();
+
+	if (cpu)
+		*cpu = p & VGETCPU_CPU_MASK;
+	if (node)
+		*node = p >> 12;
+	return 0;
+}
+
+long getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache)
+	__attribute__((weak, alias("__vdso_getcpu")));
diff --git a/kernel/arch/x86/entry/vdso/vma.c b/kernel/arch/x86/entry/vdso/vma.c
new file mode 100644
index 000000000..64df47148
--- /dev/null
+++ b/kernel/arch/x86/entry/vdso/vma.c
@@ -0,0 +1,292 @@
+/*
+ * Copyright 2007 Andi Kleen, SUSE Labs.
+ * Subject to the GPL, v.2
+ *
+ * This contains most of the x86 vDSO kernel-side code.
+ */
+#include <linux/mm.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/random.h>
+#include <linux/elf.h>
+#include <linux/cpu.h>
+#include <asm/vgtod.h>
+#include <asm/proto.h>
+#include <asm/vdso.h>
+#include <asm/vvar.h>
+#include <asm/page.h>
+#include <asm/hpet.h>
+#include <asm/desc.h>
+
+#if defined(CONFIG_X86_64)
+unsigned int __read_mostly vdso64_enabled = 1;
+#endif
+
+void __init init_vdso_image(const struct vdso_image *image)
+{
+	int i;
+	int npages = (image->size) / PAGE_SIZE;
+
+	BUG_ON(image->size % PAGE_SIZE != 0);
+	for (i = 0; i < npages; i++)
+		image->text_mapping.pages[i] =
+			virt_to_page(image->data + i*PAGE_SIZE);
+
+	apply_alternatives((struct alt_instr *)(image->data + image->alt),
+			   (struct alt_instr *)(image->data + image->alt +
+						image->alt_len));
+}
+
+struct linux_binprm;
+
+/*
+ * Put the vdso above the (randomized) stack with another randomized
+ * offset.  This way there is no hole in the middle of address space.
+ * To save memory make sure it is still in the same PTE as the stack
+ * top.  This doesn't give that many random bits.
+ *
+ * Note that this algorithm is imperfect: the distribution of the vdso
+ * start address within a PMD is biased toward the end.
+ *
+ * Only used for the 64-bit and x32 vdsos.
+ */
+static unsigned long vdso_addr(unsigned long start, unsigned len)
+{
+#ifdef CONFIG_X86_32
+	return 0;
+#else
+	unsigned long addr, end;
+	unsigned offset;
+
+	/*
+	 * Round up the start address.  It can start out unaligned as a result
+	 * of stack start randomization.
+	 */
+	start = PAGE_ALIGN(start);
+
+	/* Round the lowest possible end address up to a PMD boundary. */
+	end = (start + len + PMD_SIZE - 1) & PMD_MASK;
+	if (end >= TASK_SIZE_MAX)
+		end = TASK_SIZE_MAX;
+	end -= len;
+
+	if (end > start) {
+		offset = get_random_int() % (((end - start) >> PAGE_SHIFT) + 1);
+		addr = start + (offset << PAGE_SHIFT);
+	} else {
+		addr = start;
+	}
+
+	/*
+	 * Forcibly align the final address in case we have a hardware
+	 * issue that requires alignment for performance reasons.
+	 */
+	addr = align_vdso_addr(addr);
+
+	return addr;
+#endif
+}
+
+static int map_vdso(const struct vdso_image *image, bool calculate_addr)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	unsigned long addr, text_start;
+	int ret = 0;
+	static struct page *no_pages[] = {NULL};
+	static struct vm_special_mapping vvar_mapping = {
+		.name = "[vvar]",
+		.pages = no_pages,
+	};
+
+	if (calculate_addr) {
+		addr = vdso_addr(current->mm->start_stack,
+				 image->size - image->sym_vvar_start);
+	} else {
+		addr = 0;
+	}
+
+	down_write(&mm->mmap_sem);
+
+	addr = get_unmapped_area(NULL, addr,
+				 image->size - image->sym_vvar_start, 0, 0);
+	if (IS_ERR_VALUE(addr)) {
+		ret = addr;
+		goto up_fail;
+	}
+
+	text_start = addr - image->sym_vvar_start;
+	current->mm->context.vdso = (void __user *)text_start;
+
+	/*
+	 * MAYWRITE to allow gdb to COW and set breakpoints
+	 */
+	vma = _install_special_mapping(mm,
+				       text_start,
+				       image->size,
+				       VM_READ|VM_EXEC|
+				       VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
+				       &image->text_mapping);
+
+	if (IS_ERR(vma)) {
+		ret = PTR_ERR(vma);
+		goto up_fail;
+	}
+
+	vma = _install_special_mapping(mm,
+				       addr,
+				       -image->sym_vvar_start,
+				       VM_READ|VM_MAYREAD,
+				       &vvar_mapping);
+
+	if (IS_ERR(vma)) {
+		ret = PTR_ERR(vma);
+		goto up_fail;
+	}
+
+	if (image->sym_vvar_page)
+		ret = remap_pfn_range(vma,
+				      text_start + image->sym_vvar_page,
+				      __pa_symbol(&__vvar_page) >> PAGE_SHIFT,
+				      PAGE_SIZE,
+				      PAGE_READONLY);
+
+	if (ret)
+		goto up_fail;
+
+#ifdef CONFIG_HPET_TIMER
+	if (hpet_address && image->sym_hpet_page) {
+		ret = io_remap_pfn_range(vma,
+			text_start + image->sym_hpet_page,
+			hpet_address >> PAGE_SHIFT,
+			PAGE_SIZE,
+			pgprot_noncached(PAGE_READONLY));
+
+		if (ret)
+			goto up_fail;
+	}
+#endif
+
+up_fail:
+	if (ret)
+		current->mm->context.vdso = NULL;
+
+	up_write(&mm->mmap_sem);
+	return ret;
+}
+
+#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
+static int load_vdso32(void)
+{
+	if (vdso32_enabled != 1)  /* Other values all mean "disabled" */
+		return 0;
+
+	return map_vdso(&vdso_image_32, false);
+}
+#endif
+
+#ifdef CONFIG_X86_64
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+	if (!vdso64_enabled)
+		return 0;
+
+	return map_vdso(&vdso_image_64, true);
+}
+
+#ifdef CONFIG_COMPAT
+int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
+				       int uses_interp)
+{
+#ifdef CONFIG_X86_X32_ABI
+	if (test_thread_flag(TIF_X32)) {
+		if (!vdso64_enabled)
+			return 0;
+
+		return map_vdso(&vdso_image_x32, true);
+	}
+#endif
+#ifdef CONFIG_IA32_EMULATION
+	return load_vdso32();
+#else
+	return 0;
+#endif
+}
+#endif
+#else
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+	return load_vdso32();
+}
+#endif
+
+#ifdef CONFIG_X86_64
+static __init int vdso_setup(char *s)
+{
+	vdso64_enabled = simple_strtoul(s, NULL, 0);
+	return 0;
+}
+__setup("vdso=", vdso_setup);
+#endif
+
+#ifdef CONFIG_X86_64
+static void vgetcpu_cpu_init(void *arg)
+{
+	int cpu = smp_processor_id();
+	struct desc_struct d = { };
+	unsigned long node = 0;
+#ifdef CONFIG_NUMA
+	node = cpu_to_node(cpu);
+#endif
+	if (cpu_has(&cpu_data(cpu), X86_FEATURE_RDTSCP))
+		write_rdtscp_aux((node << 12) | cpu);
+
+	/*
+	 * Store cpu number in limit so that it can be loaded
+	 * quickly in user space in vgetcpu. (12 bits for the CPU
+	 * and 8 bits for the node)
+	 */
+	d.limit0 = cpu | ((node & 0xf) << 12);
+	d.limit = node >> 4;
+	d.type = 5;		/* RO data, expand down, accessed */
+	d.dpl = 3;		/* Visible to user code */
+	d.s = 1;		/* Not a system segment */
+	d.p = 1;		/* Present */
+	d.d = 1;		/* 32-bit */
+
+	write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_PER_CPU, &d, DESCTYPE_S);
+}
+
+static int
+vgetcpu_cpu_notifier(struct notifier_block *n, unsigned long action, void *arg)
+{
+	long cpu = (long)arg;
+
+	if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN)
+		smp_call_function_single(cpu, vgetcpu_cpu_init, NULL, 1);
+
+	return NOTIFY_DONE;
+}
+
+static int __init init_vdso(void)
+{
+	init_vdso_image(&vdso_image_64);
+
+#ifdef CONFIG_X86_X32_ABI
+	init_vdso_image(&vdso_image_x32);
+#endif
+
+	cpu_notifier_register_begin();
+
+	on_each_cpu(vgetcpu_cpu_init, NULL, 1);
+	/* notifier priority > KVM */
+	__hotcpu_notifier(vgetcpu_cpu_notifier, 30);
+
+	cpu_notifier_register_done();
+
+	return 0;
+}
+subsys_initcall(init_vdso);
+#endif /* CONFIG_X86_64 */
diff --git a/kernel/arch/x86/entry/vsyscall/Makefile b/kernel/arch/x86/entry/vsyscall/Makefile
new file mode 100644
index 000000000..a9f4856f6
--- /dev/null
+++ b/kernel/arch/x86/entry/vsyscall/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the x86 low level vsyscall code
+#
+obj-y					:= vsyscall_gtod.o
+
+obj-$(CONFIG_X86_VSYSCALL_EMULATION)	+= vsyscall_64.o vsyscall_emu_64.o
+
diff --git a/kernel/arch/x86/entry/vsyscall/vsyscall_64.c b/kernel/arch/x86/entry/vsyscall/vsyscall_64.c
new file mode 100644
index 000000000..174c25499
--- /dev/null
+++ b/kernel/arch/x86/entry/vsyscall/vsyscall_64.c
@@ -0,0 +1,342 @@
+/*
+ * Copyright (c) 2012-2014 Andy Lutomirski <luto@amacapital.net>
+ *
+ * Based on the original implementation which is:
+ *  Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
+ *  Copyright 2003 Andi Kleen, SuSE Labs.
+ *
+ *  Parts of the original code have been moved to arch/x86/vdso/vma.c
+ *
+ * This file implements vsyscall emulation.  vsyscalls are a legacy ABI:
+ * Userspace can request certain kernel services by calling fixed
+ * addresses.  This concept is problematic:
+ *
+ * - It interferes with ASLR.
+ * - It's awkward to write code that lives in kernel addresses but is
+ *   callable by userspace at fixed addresses.
+ * - The whole concept is impossible for 32-bit compat userspace.
+ * - UML cannot easily virtualize a vsyscall.
+ *
+ * As of mid-2014, I believe that there is no new userspace code that
+ * will use a vsyscall if the vDSO is present.  I hope that there will
+ * soon be no new userspace code that will ever use a vsyscall.
+ *
+ * The code in this file emulates vsyscalls when notified of a page
+ * fault to a vsyscall address.
+ */
+
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/syscalls.h>
+#include <linux/ratelimit.h>
+
+#include <asm/vsyscall.h>
+#include <asm/unistd.h>
+#include <asm/fixmap.h>
+#include <asm/traps.h>
+
+#define CREATE_TRACE_POINTS
+#include "vsyscall_trace.h"
+
+static enum { EMULATE, NATIVE, NONE } vsyscall_mode =
+#if defined(CONFIG_LEGACY_VSYSCALL_NATIVE)
+	NATIVE;
+#elif defined(CONFIG_LEGACY_VSYSCALL_NONE)
+	NONE;
+#else
+	EMULATE;
+#endif
+
+static int __init vsyscall_setup(char *str)
+{
+	if (str) {
+		if (!strcmp("emulate", str))
+			vsyscall_mode = EMULATE;
+		else if (!strcmp("native", str))
+			vsyscall_mode = NATIVE;
+		else if (!strcmp("none", str))
+			vsyscall_mode = NONE;
+		else
+			return -EINVAL;
+
+		return 0;
+	}
+
+	return -EINVAL;
+}
+early_param("vsyscall", vsyscall_setup);
+
+static void warn_bad_vsyscall(const char *level, struct pt_regs *regs,
+			      const char *message)
+{
+	if (!show_unhandled_signals)
+		return;
+
+	printk_ratelimited("%s%s[%d] %s ip:%lx cs:%lx sp:%lx ax:%lx si:%lx di:%lx\n",
+			   level, current->comm, task_pid_nr(current),
+			   message, regs->ip, regs->cs,
+			   regs->sp, regs->ax, regs->si, regs->di);
+}
+
+static int addr_to_vsyscall_nr(unsigned long addr)
+{
+	int nr;
+
+	if ((addr & ~0xC00UL) != VSYSCALL_ADDR)
+		return -EINVAL;
+
+	nr = (addr & 0xC00UL) >> 10;
+	if (nr >= 3)
+		return -EINVAL;
+
+	return nr;
+}
+
+static bool write_ok_or_segv(unsigned long ptr, size_t size)
+{
+	/*
+	 * XXX: if access_ok, get_user, and put_user handled
+	 * sig_on_uaccess_error, this could go away.
+	 */
+
+	if (!access_ok(VERIFY_WRITE, (void __user *)ptr, size)) {
+		siginfo_t info;
+		struct thread_struct *thread = &current->thread;
+
+		thread->error_code	= 6;  /* user fault, no page, write */
+		thread->cr2		= ptr;
+		thread->trap_nr		= X86_TRAP_PF;
+
+		memset(&info, 0, sizeof(info));
+		info.si_signo		= SIGSEGV;
+		info.si_errno		= 0;
+		info.si_code		= SEGV_MAPERR;
+		info.si_addr		= (void __user *)ptr;
+
+		force_sig_info(SIGSEGV, &info, current);
+		return false;
+	} else {
+		return true;
+	}
+}
+
+bool emulate_vsyscall(struct pt_regs *regs, unsigned long address)
+{
+	struct task_struct *tsk;
+	unsigned long caller;
+	int vsyscall_nr, syscall_nr, tmp;
+	int prev_sig_on_uaccess_error;
+	long ret;
+
+	/*
+	 * No point in checking CS -- the only way to get here is a user mode
+	 * trap to a high address, which means that we're in 64-bit user code.
+	 */
+
+	WARN_ON_ONCE(address != regs->ip);
+
+	if (vsyscall_mode == NONE) {
+		warn_bad_vsyscall(KERN_INFO, regs,
+				  "vsyscall attempted with vsyscall=none");
+		return false;
+	}
+
+	vsyscall_nr = addr_to_vsyscall_nr(address);
+
+	trace_emulate_vsyscall(vsyscall_nr);
+
+	if (vsyscall_nr < 0) {
+		warn_bad_vsyscall(KERN_WARNING, regs,
+				  "misaligned vsyscall (exploit attempt or buggy program) -- look up the vsyscall kernel parameter if you need a workaround");
+		goto sigsegv;
+	}
+
+	if (get_user(caller, (unsigned long __user *)regs->sp) != 0) {
+		warn_bad_vsyscall(KERN_WARNING, regs,
+				  "vsyscall with bad stack (exploit attempt?)");
+		goto sigsegv;
+	}
+
+	tsk = current;
+
+	/*
+	 * Check for access_ok violations and find the syscall nr.
+	 *
+	 * NULL is a valid user pointer (in the access_ok sense) on 32-bit and
+	 * 64-bit, so we don't need to special-case it here.  For all the
+	 * vsyscalls, NULL means "don't write anything" not "write it at
+	 * address 0".
+	 */
+	switch (vsyscall_nr) {
+	case 0:
+		if (!write_ok_or_segv(regs->di, sizeof(struct timeval)) ||
+		    !write_ok_or_segv(regs->si, sizeof(struct timezone))) {
+			ret = -EFAULT;
+			goto check_fault;
+		}
+
+		syscall_nr = __NR_gettimeofday;
+		break;
+
+	case 1:
+		if (!write_ok_or_segv(regs->di, sizeof(time_t))) {
+			ret = -EFAULT;
+			goto check_fault;
+		}
+
+		syscall_nr = __NR_time;
+		break;
+
+	case 2:
+		if (!write_ok_or_segv(regs->di, sizeof(unsigned)) ||
+		    !write_ok_or_segv(regs->si, sizeof(unsigned))) {
+			ret = -EFAULT;
+			goto check_fault;
+		}
+
+		syscall_nr = __NR_getcpu;
+		break;
+	}
+
+	/*
+	 * Handle seccomp.  regs->ip must be the original value.
+	 * See seccomp_send_sigsys and Documentation/prctl/seccomp_filter.txt.
+	 *
+	 * We could optimize the seccomp disabled case, but performance
+	 * here doesn't matter.
+	 */
+	regs->orig_ax = syscall_nr;
+	regs->ax = -ENOSYS;
+	tmp = secure_computing();
+	if ((!tmp && regs->orig_ax != syscall_nr) || regs->ip != address) {
+		warn_bad_vsyscall(KERN_DEBUG, regs,
+				  "seccomp tried to change syscall nr or ip");
+		do_exit(SIGSYS);
+	}
+	regs->orig_ax = -1;
+	if (tmp)
+		goto do_ret;  /* skip requested */
+
+	/*
+	 * With a real vsyscall, page faults cause SIGSEGV.  We want to
+	 * preserve that behavior to make writing exploits harder.
+	 */
+	prev_sig_on_uaccess_error = current_thread_info()->sig_on_uaccess_error;
+	current_thread_info()->sig_on_uaccess_error = 1;
+
+	ret = -EFAULT;
+	switch (vsyscall_nr) {
+	case 0:
+		ret = sys_gettimeofday(
+			(struct timeval __user *)regs->di,
+			(struct timezone __user *)regs->si);
+		break;
+
+	case 1:
+		ret = sys_time((time_t __user *)regs->di);
+		break;
+
+	case 2:
+		ret = sys_getcpu((unsigned __user *)regs->di,
+				 (unsigned __user *)regs->si,
+				 NULL);
+		break;
+	}
+
+	current_thread_info()->sig_on_uaccess_error = prev_sig_on_uaccess_error;
+
+check_fault:
+	if (ret == -EFAULT) {
+		/* Bad news -- userspace fed a bad pointer to a vsyscall. */
+		warn_bad_vsyscall(KERN_INFO, regs,
+				  "vsyscall fault (exploit attempt?)");
+
+		/*
+		 * If we failed to generate a signal for any reason,
+		 * generate one here.  (This should be impossible.)
+		 */
+		if (WARN_ON_ONCE(!sigismember(&tsk->pending.signal, SIGBUS) &&
+				 !sigismember(&tsk->pending.signal, SIGSEGV)))
+			goto sigsegv;
+
+		return true;  /* Don't emulate the ret. */
+	}
+
+	regs->ax = ret;
+
+do_ret:
+	/* Emulate a ret instruction. */
+	regs->ip = caller;
+	regs->sp += 8;
+	return true;
+
+sigsegv:
+	force_sig(SIGSEGV, current);
+	return true;
+}
+
+/*
+ * A pseudo VMA to allow ptrace access for the vsyscall page.  This only
+ * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
+ * not need special handling anymore:
+ */
+static const char *gate_vma_name(struct vm_area_struct *vma)
+{
+	return "[vsyscall]";
+}
+static const struct vm_operations_struct gate_vma_ops = {
+	.name = gate_vma_name,
+};
+static struct vm_area_struct gate_vma = {
+	.vm_start	= VSYSCALL_ADDR,
+	.vm_end		= VSYSCALL_ADDR + PAGE_SIZE,
+	.vm_page_prot	= PAGE_READONLY_EXEC,
+	.vm_flags	= VM_READ | VM_EXEC,
+	.vm_ops		= &gate_vma_ops,
+};
+
+struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
+{
+#ifdef CONFIG_COMPAT
+	if (!mm || mm->context.ia32_compat)
+		return NULL;
+#endif
+	if (vsyscall_mode == NONE)
+		return NULL;
+	return &gate_vma;
+}
+
+int in_gate_area(struct mm_struct *mm, unsigned long addr)
+{
+	struct vm_area_struct *vma = get_gate_vma(mm);
+
+	if (!vma)
+		return 0;
+
+	return (addr >= vma->vm_start) && (addr < vma->vm_end);
+}
+
+/*
+ * Use this when you have no reliable mm, typically from interrupt
+ * context. It is less reliable than using a task's mm and may give
+ * false positives.
+ */
+int in_gate_area_no_mm(unsigned long addr)
+{
+	return vsyscall_mode != NONE && (addr & PAGE_MASK) == VSYSCALL_ADDR;
+}
+
+void __init map_vsyscall(void)
+{
+	extern char __vsyscall_page;
+	unsigned long physaddr_vsyscall = __pa_symbol(&__vsyscall_page);
+
+	if (vsyscall_mode != NONE)
+		__set_fixmap(VSYSCALL_PAGE, physaddr_vsyscall,
+			     vsyscall_mode == NATIVE
+			     ? PAGE_KERNEL_VSYSCALL
+			     : PAGE_KERNEL_VVAR);
+
+	BUILD_BUG_ON((unsigned long)__fix_to_virt(VSYSCALL_PAGE) !=
+		     (unsigned long)VSYSCALL_ADDR);
+}
diff --git a/kernel/arch/x86/entry/vsyscall/vsyscall_emu_64.S b/kernel/arch/x86/entry/vsyscall/vsyscall_emu_64.S
new file mode 100644
index 000000000..c9596a9af
--- /dev/null
+++ b/kernel/arch/x86/entry/vsyscall/vsyscall_emu_64.S
@@ -0,0 +1,37 @@
+/*
+ * vsyscall_emu_64.S: Vsyscall emulation page
+ *
+ * Copyright (c) 2011 Andy Lutomirski
+ *
+ * Subject to the GNU General Public License, version 2
+ */
+
+#include <linux/linkage.h>
+
+#include <asm/irq_vectors.h>
+#include <asm/page_types.h>
+#include <asm/unistd_64.h>
+
+__PAGE_ALIGNED_DATA
+	.globl __vsyscall_page
+	.balign PAGE_SIZE, 0xcc
+	.type __vsyscall_page, @object
+__vsyscall_page:
+
+	mov $__NR_gettimeofday, %rax
+	syscall
+	ret
+
+	.balign 1024, 0xcc
+	mov $__NR_time, %rax
+	syscall
+	ret
+
+	.balign 1024, 0xcc
+	mov $__NR_getcpu, %rax
+	syscall
+	ret
+
+	.balign 4096, 0xcc
+
+	.size __vsyscall_page, 4096
diff --git a/kernel/arch/x86/entry/vsyscall/vsyscall_gtod.c b/kernel/arch/x86/entry/vsyscall/vsyscall_gtod.c
new file mode 100644
index 000000000..51e330416
--- /dev/null
+++ b/kernel/arch/x86/entry/vsyscall/vsyscall_gtod.c
@@ -0,0 +1,70 @@
+/*
+ *  Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
+ *  Copyright 2003 Andi Kleen, SuSE Labs.
+ *
+ *  Modified for x86 32 bit architecture by
+ *  Stefani Seibold <stefani@seibold.net>
+ *  sponsored by Rohde & Schwarz GmbH & Co. KG Munich/Germany
+ *
+ *  Thanks to hpa@transmeta.com for some useful hint.
+ *  Special thanks to Ingo Molnar for his early experience with
+ *  a different vsyscall implementation for Linux/IA32 and for the name.
+ *
+ */
+
+#include <linux/timekeeper_internal.h>
+#include <asm/vgtod.h>
+#include <asm/vvar.h>
+
+DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data);
+
+void update_vsyscall_tz(void)
+{
+	vsyscall_gtod_data.tz_minuteswest = sys_tz.tz_minuteswest;
+	vsyscall_gtod_data.tz_dsttime = sys_tz.tz_dsttime;
+}
+
+void update_vsyscall(struct timekeeper *tk)
+{
+	struct vsyscall_gtod_data *vdata = &vsyscall_gtod_data;
+
+	gtod_write_begin(vdata);
+
+	/* copy vsyscall data */
+	vdata->vclock_mode	= tk->tkr_mono.clock->archdata.vclock_mode;
+	vdata->cycle_last	= tk->tkr_mono.cycle_last;
+	vdata->mask		= tk->tkr_mono.mask;
+	vdata->mult		= tk->tkr_mono.mult;
+	vdata->shift		= tk->tkr_mono.shift;
+
+	vdata->wall_time_sec		= tk->xtime_sec;
+	vdata->wall_time_snsec		= tk->tkr_mono.xtime_nsec;
+
+	vdata->monotonic_time_sec	= tk->xtime_sec
+					+ tk->wall_to_monotonic.tv_sec;
+	vdata->monotonic_time_snsec	= tk->tkr_mono.xtime_nsec
+					+ ((u64)tk->wall_to_monotonic.tv_nsec
+						<< tk->tkr_mono.shift);
+	while (vdata->monotonic_time_snsec >=
+					(((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) {
+		vdata->monotonic_time_snsec -=
+					((u64)NSEC_PER_SEC) << tk->tkr_mono.shift;
+		vdata->monotonic_time_sec++;
+	}
+
+	vdata->wall_time_coarse_sec	= tk->xtime_sec;
+	vdata->wall_time_coarse_nsec	= (long)(tk->tkr_mono.xtime_nsec >>
+						 tk->tkr_mono.shift);
+
+	vdata->monotonic_time_coarse_sec =
+		vdata->wall_time_coarse_sec + tk->wall_to_monotonic.tv_sec;
+	vdata->monotonic_time_coarse_nsec =
+		vdata->wall_time_coarse_nsec + tk->wall_to_monotonic.tv_nsec;
+
+	while (vdata->monotonic_time_coarse_nsec >= NSEC_PER_SEC) {
+		vdata->monotonic_time_coarse_nsec -= NSEC_PER_SEC;
+		vdata->monotonic_time_coarse_sec++;
+	}
+
+	gtod_write_end(vdata);
+}
diff --git a/kernel/arch/x86/entry/vsyscall/vsyscall_trace.h b/kernel/arch/x86/entry/vsyscall/vsyscall_trace.h
new file mode 100644
index 000000000..9dd7359a3
--- /dev/null
+++ b/kernel/arch/x86/entry/vsyscall/vsyscall_trace.h
@@ -0,0 +1,29 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM vsyscall
+
+#if !defined(__VSYSCALL_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define __VSYSCALL_TRACE_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(emulate_vsyscall,
+
+	    TP_PROTO(int nr),
+
+	    TP_ARGS(nr),
+
+	    TP_STRUCT__entry(__field(int, nr)),
+
+	    TP_fast_assign(
+			   __entry->nr = nr;
+			   ),
+
+	    TP_printk("nr = %d", __entry->nr)
+);
+
+#endif
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH ../../arch/x86/entry/vsyscall/
+#define TRACE_INCLUDE_FILE vsyscall_trace
+#include <trace/define_trace.h>