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Diffstat (limited to 'arch/x86/kernel/dumpstack_64.c')
-rw-r--r--arch/x86/kernel/dumpstack_64.c118
1 files changed, 84 insertions, 34 deletions
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index addb207dab92..1abcb50b48ae 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -104,6 +104,44 @@ in_irq_stack(unsigned long *stack, unsigned long *irq_stack,
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
@@ -116,12 +154,12 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
const struct stacktrace_ops *ops, void *data)
{
const unsigned cpu = get_cpu();
- unsigned long *irq_stack_end =
- (unsigned long *)per_cpu(irq_stack_ptr, cpu);
- unsigned used = 0;
struct thread_info *tinfo;
- int graph = 0;
+ 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;
@@ -143,49 +181,61 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
* exceptions
*/
tinfo = task_thread_info(task);
- for (;;) {
+ while (!done) {
+ unsigned long *stack_end;
+ enum stack_type stype;
char *id;
- unsigned long *estack_end;
- estack_end = in_exception_stack(cpu, (unsigned long)stack,
- &used, &id);
- if (estack_end) {
+ 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, estack_end, &graph);
+ 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 *) estack_end[-2];
- continue;
- }
- if (irq_stack_end) {
- unsigned long *irq_stack;
- irq_stack = irq_stack_end -
- (IRQ_STACK_SIZE - 64) / sizeof(*irq_stack);
-
- if (in_irq_stack(stack, irq_stack, irq_stack_end)) {
- if (ops->stack(data, "IRQ") < 0)
- break;
- bp = ops->walk_stack(tinfo, stack, bp,
- ops, data, irq_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 *) (irq_stack_end[-1]);
- irq_stack_end = NULL;
- ops->stack(data, "EOI");
- continue;
- }
+ 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;
}
- break;
}
/*