diff options
Diffstat (limited to 'arch/parisc/kernel/irq.c')
| -rw-r--r-- | arch/parisc/kernel/irq.c | 31 |
1 files changed, 29 insertions, 2 deletions
diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c index 8094d3ed3b64..61e51ac85659 100644 --- a/arch/parisc/kernel/irq.c +++ b/arch/parisc/kernel/irq.c @@ -330,6 +330,34 @@ static inline int eirr_to_irq(unsigned long eirr) return (BITS_PER_LONG - bit) + TIMER_IRQ; } +int sysctl_panic_on_stackoverflow = 1; + +static inline void stack_overflow_check(struct pt_regs *regs) +{ +#ifdef CONFIG_DEBUG_STACKOVERFLOW + #define STACK_MARGIN (256*6) + + /* Our stack starts directly behind the thread_info struct. */ + unsigned long stack_start = (unsigned long) current_thread_info(); + unsigned long sp = regs->gr[30]; + + /* if sr7 != 0, we interrupted a userspace process which we do not want + * to check for stack overflow. We will only check the kernel stack. */ + if (regs->sr[7]) + return; + + if (likely((sp - stack_start) < (THREAD_SIZE - STACK_MARGIN))) + return; + + pr_emerg("stackcheck: %s will most likely overflow kernel stack " + "(sp:%lx, stk bottom-top:%lx-%lx)\n", + current->comm, sp, stack_start, stack_start + THREAD_SIZE); + + if (sysctl_panic_on_stackoverflow) + panic("low stack detected by irq handler - check messages\n"); +#endif +} + /* ONLY called from entry.S:intr_extint() */ void do_cpu_irq_mask(struct pt_regs *regs) { @@ -364,6 +392,7 @@ void do_cpu_irq_mask(struct pt_regs *regs) goto set_out; } #endif + stack_overflow_check(regs); generic_handle_irq(irq); out: @@ -420,6 +449,4 @@ void __init init_IRQ(void) cpu_eiem = EIEM_MASK(TIMER_IRQ); #endif set_eiem(cpu_eiem); /* EIEM : enable all external intr */ - } - |