1 files changed, 14 insertions, 28 deletions

diff --git a/kernel/arch/x86/include/asm/thread_info.h b/kernel/arch/x86/include/asm/thread_info.h
index 606144afb..ddb63bd90 100644
--- a/kernel/arch/x86/include/asm/thread_info.h
+++ b/kernel/arch/x86/include/asm/thread_info.h
@@ -27,14 +27,17 @@
  * Without this offset, that can result in a page fault.  (We are
  * careful that, in this case, the value we read doesn't matter.)
  *
- * In vm86 mode, the hardware frame is much longer still, but we neither
- * access the extra members from NMI context, nor do we write such a
- * frame at sp0 at all.
+ * In vm86 mode, the hardware frame is much longer still, so add 16
+ * bytes to make room for the real-mode segments.
  *
  * x86_64 has a fixed-length stack frame.
  */
 #ifdef CONFIG_X86_32
-# define TOP_OF_KERNEL_STACK_PADDING 8
+# ifdef CONFIG_VM86
+#  define TOP_OF_KERNEL_STACK_PADDING 16
+# else
+#  define TOP_OF_KERNEL_STACK_PADDING 8
+# endif
 #else
 # define TOP_OF_KERNEL_STACK_PADDING 0
 #endif
@@ -54,11 +57,9 @@ struct thread_info {
 	__u32			flags;		/* low level flags */
 	__u32			status;		/* thread synchronous flags */
 	__u32			cpu;		/* current CPU */
-	int			saved_preempt_count;
-	int			preempt_lazy_count;	/* 0 => lazy preemptable
-							 <0  => BUG */
 	mm_segment_t		addr_limit;
-	void __user		*sysenter_return;
+	int			preempt_lazy_count;	/* 0 => lazy preemptable
+							  <0 => BUG */
 	unsigned int		sig_on_uaccess_error:1;
 	unsigned int		uaccess_err:1;	/* uaccess failed */
 };
@@ -68,7 +69,6 @@ struct thread_info {
 	.task		= &tsk,			\
 	.flags		= 0,			\
 	.cpu		= 0,			\
-	.saved_preempt_count = INIT_PREEMPT_COUNT,	\
 	.addr_limit	= KERNEL_DS,		\
 }
 
@@ -144,27 +144,11 @@ struct thread_info {
 	 _TIF_SECCOMP | _TIF_SINGLESTEP | _TIF_SYSCALL_TRACEPOINT |	\
 	 _TIF_NOHZ)
 
-/* work to do in syscall_trace_leave() */
-#define _TIF_WORK_SYSCALL_EXIT	\
-	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP |	\
-	 _TIF_SYSCALL_TRACEPOINT | _TIF_NOHZ)
-
-/* work to do on interrupt/exception return */
-#define _TIF_WORK_MASK							\
-	(0x0000FFFF &							\
-	 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|			\
-	   _TIF_SINGLESTEP|_TIF_SECCOMP|_TIF_SYSCALL_EMU))
-
 /* work to do on any return to user space */
 #define _TIF_ALLWORK_MASK						\
 	((0x0000FFFF & ~_TIF_SECCOMP) | _TIF_SYSCALL_TRACEPOINT |	\
 	_TIF_NOHZ)
 
-/* Only used for 64 bit */
-#define _TIF_DO_NOTIFY_MASK						\
-	(_TIF_SIGPENDING | _TIF_NOTIFY_RESUME |				\
-	 _TIF_USER_RETURN_NOTIFY | _TIF_UPROBE)
-
 /* flags to check in __switch_to() */
 #define _TIF_WORK_CTXSW							\
 	(_TIF_IO_BITMAP|_TIF_NOTSC|_TIF_BLOCKSTEP)
@@ -183,8 +167,6 @@ struct thread_info {
  */
 #ifndef __ASSEMBLY__
 
-DECLARE_PER_CPU(unsigned long, kernel_stack);
-
 static inline struct thread_info *current_thread_info(void)
 {
 	return (struct thread_info *)(current_top_of_stack() - THREAD_SIZE);
@@ -203,9 +185,13 @@ static inline unsigned long current_stack_pointer(void)
 
 #else /* !__ASSEMBLY__ */
 
+#ifdef CONFIG_X86_64
+# define cpu_current_top_of_stack (cpu_tss + TSS_sp0)
+#endif
+
 /* Load thread_info address into "reg" */
 #define GET_THREAD_INFO(reg) \
-	_ASM_MOV PER_CPU_VAR(kernel_stack),reg ; \
+	_ASM_MOV PER_CPU_VAR(cpu_current_top_of_stack),reg ; \
 	_ASM_SUB $(THREAD_SIZE),reg ;
 
 /*