Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 354 insertions, 0 deletions

diff --git a/kernel/arch/x86/kernel/dumpstack_64.c b/kernel/arch/x86/kernel/dumpstack_64.c
new file mode 100644
index 000000000..5f1c6266e
--- /dev/null
+++ b/kernel/arch/x86/kernel/dumpstack_64.c
@@ -0,0 +1,354 @@
+/*
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *  Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
+ */
+#include <linux/kallsyms.h>
+#include <linux/kprobes.h>
+#include <linux/uaccess.h>
+#include <linux/hardirq.h>
+#include <linux/kdebug.h>
+#include <linux/module.h>
+#include <linux/ptrace.h>
+#include <linux/kexec.h>
+#include <linux/sysfs.h>
+#include <linux/bug.h>
+#include <linux/nmi.h>
+
+#include <asm/stacktrace.h>
+
+
+#define N_EXCEPTION_STACKS_END \
+		(N_EXCEPTION_STACKS + DEBUG_STKSZ/EXCEPTION_STKSZ - 2)
+
+static char x86_stack_ids[][8] = {
+		[ DEBUG_STACK-1			]	= "#DB",
+		[ NMI_STACK-1			]	= "NMI",
+		[ DOUBLEFAULT_STACK-1		]	= "#DF",
+		[ MCE_STACK-1			]	= "#MC",
+#if DEBUG_STKSZ > EXCEPTION_STKSZ
+		[ N_EXCEPTION_STACKS ...
+		  N_EXCEPTION_STACKS_END	]	= "#DB[?]"
+#endif
+};
+
+static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
+					 unsigned *usedp, char **idp)
+{
+	unsigned k;
+
+	/*
+	 * Iterate over all exception stacks, and figure out whether
+	 * 'stack' is in one of them:
+	 */
+	for (k = 0; k < N_EXCEPTION_STACKS; k++) {
+		unsigned long end = per_cpu(orig_ist, cpu).ist[k];
+		/*
+		 * Is 'stack' above this exception frame's end?
+		 * If yes then skip to the next frame.
+		 */
+		if (stack >= end)
+			continue;
+		/*
+		 * Is 'stack' above this exception frame's start address?
+		 * If yes then we found the right frame.
+		 */
+		if (stack >= end - EXCEPTION_STKSZ) {
+			/*
+			 * Make sure we only iterate through an exception
+			 * stack once. If it comes up for the second time
+			 * then there's something wrong going on - just
+			 * break out and return NULL:
+			 */
+			if (*usedp & (1U << k))
+				break;
+			*usedp |= 1U << k;
+			*idp = x86_stack_ids[k];
+			return (unsigned long *)end;
+		}
+		/*
+		 * If this is a debug stack, and if it has a larger size than
+		 * the usual exception stacks, then 'stack' might still
+		 * be within the lower portion of the debug stack:
+		 */
+#if DEBUG_STKSZ > EXCEPTION_STKSZ
+		if (k == DEBUG_STACK - 1 && stack >= end - DEBUG_STKSZ) {
+			unsigned j = N_EXCEPTION_STACKS - 1;
+
+			/*
+			 * Black magic. A large debug stack is composed of
+			 * multiple exception stack entries, which we
+			 * iterate through now. Dont look:
+			 */
+			do {
+				++j;
+				end -= EXCEPTION_STKSZ;
+				x86_stack_ids[j][4] = '1' +
+						(j - N_EXCEPTION_STACKS);
+			} while (stack < end - EXCEPTION_STKSZ);
+			if (*usedp & (1U << j))
+				break;
+			*usedp |= 1U << j;
+			*idp = x86_stack_ids[j];
+			return (unsigned long *)end;
+		}
+#endif
+	}
+	return NULL;
+}
+
+static inline int
+in_irq_stack(unsigned long *stack, unsigned long *irq_stack,
+	     unsigned long *irq_stack_end)
+{
+	return (stack >= irq_stack && stack < irq_stack_end);
+}
+
+static const unsigned long irq_stack_size =
+	(IRQ_STACK_SIZE - 64) / sizeof(unsigned long);
+
+enum stack_type {
+	STACK_IS_UNKNOWN,
+	STACK_IS_NORMAL,
+	STACK_IS_EXCEPTION,
+	STACK_IS_IRQ,
+};
+
+static enum stack_type
+analyze_stack(int cpu, struct task_struct *task, unsigned long *stack,
+	      unsigned long **stack_end, unsigned long *irq_stack,
+	      unsigned *used, char **id)
+{
+	unsigned long addr;
+
+	addr = ((unsigned long)stack & (~(THREAD_SIZE - 1)));
+	if ((unsigned long)task_stack_page(task) == addr)
+		return STACK_IS_NORMAL;
+
+	*stack_end = in_exception_stack(cpu, (unsigned long)stack,
+					used, id);
+	if (*stack_end)
+		return STACK_IS_EXCEPTION;
+
+	if (!irq_stack)
+		return STACK_IS_NORMAL;
+
+	*stack_end = irq_stack;
+	irq_stack = irq_stack - irq_stack_size;
+
+	if (in_irq_stack(stack, irq_stack, *stack_end))
+		return STACK_IS_IRQ;
+
+	return STACK_IS_UNKNOWN;
+}
+
+/*
+ * x86-64 can have up to three kernel stacks:
+ * process stack
+ * interrupt stack
+ * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
+ */
+
+void dump_trace(struct task_struct *task, struct pt_regs *regs,
+		unsigned long *stack, unsigned long bp,
+		const struct stacktrace_ops *ops, void *data)
+{
+	const unsigned cpu = get_cpu();
+	struct thread_info *tinfo;
+	unsigned long *irq_stack = (unsigned long *)per_cpu(irq_stack_ptr, cpu);
+	unsigned long dummy;
+	unsigned used = 0;
+	int graph = 0;
+	int done = 0;
+
+	if (!task)
+		task = current;
+
+	if (!stack) {
+		if (regs)
+			stack = (unsigned long *)regs->sp;
+		else if (task != current)
+			stack = (unsigned long *)task->thread.sp;
+		else
+			stack = &dummy;
+	}
+
+	if (!bp)
+		bp = stack_frame(task, regs);
+	/*
+	 * Print function call entries in all stacks, starting at the
+	 * current stack address. If the stacks consist of nested
+	 * exceptions
+	 */
+	tinfo = task_thread_info(task);
+	while (!done) {
+		unsigned long *stack_end;
+		enum stack_type stype;
+		char *id;
+
+		stype = analyze_stack(cpu, task, stack, &stack_end,
+				      irq_stack, &used, &id);
+
+		/* Default finish unless specified to continue */
+		done = 1;
+
+		switch (stype) {
+
+		/* Break out early if we are on the thread stack */
+		case STACK_IS_NORMAL:
+			break;
+
+		case STACK_IS_EXCEPTION:
+
+			if (ops->stack(data, id) < 0)
+				break;
+
+			bp = ops->walk_stack(tinfo, stack, bp, ops,
+					     data, stack_end, &graph);
+			ops->stack(data, "<EOE>");
+			/*
+			 * We link to the next stack via the
+			 * second-to-last pointer (index -2 to end) in the
+			 * exception stack:
+			 */
+			stack = (unsigned long *) stack_end[-2];
+			done = 0;
+			break;
+
+		case STACK_IS_IRQ:
+
+			if (ops->stack(data, "IRQ") < 0)
+				break;
+			bp = ops->walk_stack(tinfo, stack, bp,
+				     ops, data, stack_end, &graph);
+			/*
+			 * We link to the next stack (which would be
+			 * the process stack normally) the last
+			 * pointer (index -1 to end) in the IRQ stack:
+			 */
+			stack = (unsigned long *) (stack_end[-1]);
+			irq_stack = NULL;
+			ops->stack(data, "EOI");
+			done = 0;
+			break;
+
+		case STACK_IS_UNKNOWN:
+			ops->stack(data, "UNK");
+			break;
+		}
+	}
+
+	/*
+	 * This handles the process stack:
+	 */
+	bp = ops->walk_stack(tinfo, stack, bp, ops, data, NULL, &graph);
+	put_cpu();
+}
+EXPORT_SYMBOL(dump_trace);
+
+void
+show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
+		   unsigned long *sp, unsigned long bp, char *log_lvl)
+{
+	unsigned long *irq_stack_end;
+	unsigned long *irq_stack;
+	unsigned long *stack;
+	int cpu;
+	int i;
+
+	preempt_disable();
+	cpu = smp_processor_id();
+
+	irq_stack_end	= (unsigned long *)(per_cpu(irq_stack_ptr, cpu));
+	irq_stack	= (unsigned long *)(per_cpu(irq_stack_ptr, cpu) - IRQ_STACK_SIZE);
+
+	/*
+	 * Debugging aid: "show_stack(NULL, NULL);" prints the
+	 * back trace for this cpu:
+	 */
+	if (sp == NULL) {
+		if (task)
+			sp = (unsigned long *)task->thread.sp;
+		else
+			sp = (unsigned long *)&sp;
+	}
+
+	stack = sp;
+	for (i = 0; i < kstack_depth_to_print; i++) {
+		if (stack >= irq_stack && stack <= irq_stack_end) {
+			if (stack == irq_stack_end) {
+				stack = (unsigned long *) (irq_stack_end[-1]);
+				pr_cont(" <EOI> ");
+			}
+		} else {
+		if (kstack_end(stack))
+			break;
+		}
+		if ((i % STACKSLOTS_PER_LINE) == 0) {
+			if (i != 0)
+				pr_cont("\n");
+			printk("%s %016lx", log_lvl, *stack++);
+		} else
+			pr_cont(" %016lx", *stack++);
+		touch_nmi_watchdog();
+	}
+	preempt_enable();
+
+	pr_cont("\n");
+	show_trace_log_lvl(task, regs, sp, bp, log_lvl);
+}
+
+void show_regs(struct pt_regs *regs)
+{
+	int i;
+	unsigned long sp;
+
+	sp = regs->sp;
+	show_regs_print_info(KERN_DEFAULT);
+	__show_regs(regs, 1);
+
+	/*
+	 * When in-kernel, we also print out the stack and code at the
+	 * time of the fault..
+	 */
+	if (!user_mode(regs)) {
+		unsigned int code_prologue = code_bytes * 43 / 64;
+		unsigned int code_len = code_bytes;
+		unsigned char c;
+		u8 *ip;
+
+		printk(KERN_DEFAULT "Stack:\n");
+		show_stack_log_lvl(NULL, regs, (unsigned long *)sp,
+				   0, KERN_DEFAULT);
+
+		printk(KERN_DEFAULT "Code: ");
+
+		ip = (u8 *)regs->ip - code_prologue;
+		if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
+			/* try starting at IP */
+			ip = (u8 *)regs->ip;
+			code_len = code_len - code_prologue + 1;
+		}
+		for (i = 0; i < code_len; i++, ip++) {
+			if (ip < (u8 *)PAGE_OFFSET ||
+					probe_kernel_address(ip, c)) {
+				pr_cont(" Bad RIP value.");
+				break;
+			}
+			if (ip == (u8 *)regs->ip)
+				pr_cont("<%02x> ", c);
+			else
+				pr_cont("%02x ", c);
+		}
+	}
+	pr_cont("\n");
+}
+
+int is_valid_bugaddr(unsigned long ip)
+{
+	unsigned short ud2;
+
+	if (__copy_from_user(&ud2, (const void __user *) ip, sizeof(ud2)))
+		return 0;
+
+	return ud2 == 0x0b0f;
+}