[PATCH v3 16/19] x86/irq/64: In the stack overflow warning, print the offending IP

From: Andy Lutomirski
Date: Thu Nov 23 2017 - 23:34:31 EST


In case something goes wrong with unwind (not unlikely in case of
overflow), print the offending IP where we detected the overflow.

Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
---
arch/x86/kernel/irq_64.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
index 020efbf5786b..d86e344f5b3d 100644
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -57,10 +57,10 @@ static inline void stack_overflow_check(struct pt_regs *regs)
if (regs->sp >= estack_top && regs->sp <= estack_bottom)
return;

- WARN_ONCE(1, "do_IRQ(): %s has overflown the kernel stack (cur:%Lx,sp:%lx,irq stk top-bottom:%Lx-%Lx,exception stk top-bottom:%Lx-%Lx)\n",
+ WARN_ONCE(1, "do_IRQ(): %s has overflown the kernel stack (cur:%Lx,sp:%lx,irq stk top-bottom:%Lx-%Lx,exception stk top-bottom:%Lx-%Lx,ip:%pF)\n",
current->comm, curbase, regs->sp,
irq_stack_top, irq_stack_bottom,
- estack_top, estack_bottom);
+ estack_top, estack_bottom, (void *)regs->ip);

if (sysctl_panic_on_stackoverflow)
panic("low stack detected by irq handler - check messages\n");
--
2.13.6