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-rw-r--r--arch/x86/kernel/dumpstack_64.c354
1 files changed, 354 insertions, 0 deletions
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
new file mode 100644
index 000000000..5f1c6266e
--- /dev/null
+++ b/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;
+}
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