aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/irq_64.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/irq_64.c')
-rw-r--r--arch/x86/kernel/irq_64.c35
1 files changed, 29 insertions, 6 deletions
diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
index 69bca468c47..d04d3ecded6 100644
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -26,6 +26,8 @@ EXPORT_PER_CPU_SYMBOL(irq_stat);
DEFINE_PER_CPU(struct pt_regs *, irq_regs);
EXPORT_PER_CPU_SYMBOL(irq_regs);
+int sysctl_panic_on_stackoverflow;
+
/*
* Probabilistic stack overflow check:
*
@@ -36,18 +38,39 @@ EXPORT_PER_CPU_SYMBOL(irq_regs);
static inline void stack_overflow_check(struct pt_regs *regs)
{
#ifdef CONFIG_DEBUG_STACKOVERFLOW
+#define STACK_TOP_MARGIN 128
+ struct orig_ist *oist;
+ u64 irq_stack_top, irq_stack_bottom;
+ u64 estack_top, estack_bottom;
u64 curbase = (u64)task_stack_page(current);
if (user_mode_vm(regs))
return;
- WARN_ONCE(regs->sp >= curbase &&
- regs->sp <= curbase + THREAD_SIZE &&
- regs->sp < curbase + sizeof(struct thread_info) +
- sizeof(struct pt_regs) + 128,
+ if (regs->sp >= curbase + sizeof(struct thread_info) +
+ sizeof(struct pt_regs) + STACK_TOP_MARGIN &&
+ regs->sp <= curbase + THREAD_SIZE)
+ return;
+
+ irq_stack_top = (u64)__get_cpu_var(irq_stack_union.irq_stack) +
+ STACK_TOP_MARGIN;
+ irq_stack_bottom = (u64)__get_cpu_var(irq_stack_ptr);
+ if (regs->sp >= irq_stack_top && regs->sp <= irq_stack_bottom)
+ return;
+
+ oist = &__get_cpu_var(orig_ist);
+ estack_top = (u64)oist->ist[0] - EXCEPTION_STKSZ + STACK_TOP_MARGIN;
+ estack_bottom = (u64)oist->ist[N_EXCEPTION_STACKS - 1];
+ 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",
+ current->comm, curbase, regs->sp,
+ irq_stack_top, irq_stack_bottom,
+ estack_top, estack_bottom);
- "do_IRQ: %s near stack overflow (cur:%Lx,sp:%lx)\n",
- current->comm, curbase, regs->sp);
+ if (sysctl_panic_on_stackoverflow)
+ panic("low stack detected by irq handler - check messages\n");
#endif
}