diff options
| -rw-r--r-- | arch/x86_64/Kconfig.debug | 7 | ||||
| -rw-r--r-- | arch/x86_64/kernel/irq.c | 28 |
2 files changed, 34 insertions, 1 deletions
diff --git a/arch/x86_64/Kconfig.debug b/arch/x86_64/Kconfig.debug index 0226f08be87..087a04868b2 100644 --- a/arch/x86_64/Kconfig.debug +++ b/arch/x86_64/Kconfig.debug @@ -35,6 +35,13 @@ config IOMMU_LEAK Add a simple leak tracer to the IOMMU code. This is useful when you are debugging a buggy device driver that leaks IOMMU mappings. +config DEBUG_STACKOVERFLOW + bool "Check for stack overflows" + depends on DEBUG_KERNEL + help + This option will cause messages to be printed if free stack space + drops below a certain limit. + #config X86_REMOTE_DEBUG # bool "kgdb debugging stub" diff --git a/arch/x86_64/kernel/irq.c b/arch/x86_64/kernel/irq.c index 207ecdc3982..59518d4d435 100644 --- a/arch/x86_64/kernel/irq.c +++ b/arch/x86_64/kernel/irq.c @@ -26,6 +26,30 @@ atomic_t irq_mis_count; #endif #endif +#ifdef CONFIG_DEBUG_STACKOVERFLOW +/* + * Probabilistic stack overflow check: + * + * Only check the stack in process context, because everything else + * runs on the big interrupt stacks. Checking reliably is too expensive, + * so we just check from interrupts. + */ +static inline void stack_overflow_check(struct pt_regs *regs) +{ + u64 curbase = (u64) current->thread_info; + static unsigned long warned = -60*HZ; + + if (regs->rsp >= curbase && regs->rsp <= curbase + THREAD_SIZE && + regs->rsp < curbase + sizeof(struct thread_info) + 128 && + time_after(jiffies, warned + 60*HZ)) { + printk("do_IRQ: %s near stack overflow (cur:%Lx,rsp:%lx)\n", + current->comm, curbase, regs->rsp); + show_stack(NULL,NULL); + warned = jiffies; + } +} +#endif + /* * Generic, controller-independent functions: */ @@ -96,7 +120,9 @@ asmlinkage unsigned int do_IRQ(struct pt_regs *regs) exit_idle(); irq_enter(); - +#ifdef CONFIG_DEBUG_STACKOVERFLOW + stack_overflow_check(regs); +#endif __do_IRQ(irq, regs); irq_exit(); |