The percpu irq_stack_ptr variable has a 64-byte gap from the end of the
allocated irq stack area, so subtracting IRQ_STACK_SIZE from it actually
results in a value 64 bytes before the beginning of the stack. Use
IRQ_USABLE_STACK_SIZE instead.
Signed-off-by: Josh Poimboeuf <jpoim...@redhat.com>
---
arch/x86/kernel/dumpstack_64.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index 7ea6ed0..0fdd371 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -253,8 +253,8 @@ show_stack_log_lvl(struct task_struct *task, struct pt_regs
*regs,
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);
+ irq_stack_end = (unsigned long *)(per_cpu(irq_stack_ptr, cpu));
+ irq_stack = irq_stack_end - (IRQ_USABLE_STACK_SIZE / sizeof(long));
/*
* Debugging aid: "show_stack(NULL, NULL);" prints the
--
2.7.4
