summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/dumpstack_64.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/dumpstack_64.c')
-rw-r--r--arch/x86/kernel/dumpstack_64.c33
1 files changed, 32 insertions, 1 deletions
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index 8e74093..b13af53 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -103,6 +103,35 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
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);
+}
+
+/*
+ * We are returning from the irq stack and go to the previous one.
+ * If the previous stack is also in the irq stack, then bp in the first
+ * frame of the irq stack points to the previous, interrupted one.
+ * Otherwise we have another level of indirection: We first save
+ * the bp of the previous stack, then we switch the stack to the irq one
+ * and save a new bp that links to the previous one.
+ * (See save_args())
+ */
+static inline unsigned long
+fixup_bp_irq_link(unsigned long bp, unsigned long *stack,
+ unsigned long *irq_stack, unsigned long *irq_stack_end)
+{
+#ifdef CONFIG_FRAME_POINTER
+ struct stack_frame *frame = (struct stack_frame *)bp;
+
+ if (!in_irq_stack(stack, irq_stack, irq_stack_end))
+ return (unsigned long)frame->next_frame;
+#endif
+ return bp;
+}
+
/*
* x86-64 can have up to three kernel stacks:
* process stack
@@ -175,7 +204,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
irq_stack = irq_stack_end -
(IRQ_STACK_SIZE - 64) / sizeof(*irq_stack);
- if (stack >= irq_stack && stack < irq_stack_end) {
+ if (in_irq_stack(stack, irq_stack, irq_stack_end)) {
if (ops->stack(data, "IRQ") < 0)
break;
bp = print_context_stack(tinfo, stack, bp,
@@ -186,6 +215,8 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
* pointer (index -1 to end) in the IRQ stack:
*/
stack = (unsigned long *) (irq_stack_end[-1]);
+ bp = fixup_bp_irq_link(bp, stack, irq_stack,
+ irq_stack_end);
irq_stack_end = NULL;
ops->stack(data, "EOI");
continue;