diff options
| author | H. Peter Anvin <hpa@linux.intel.com> | 2012-01-19 12:56:50 -0800 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2012-01-19 12:56:50 -0800 |
| commit | 282f445a779ed76fca9884fe377bf56a3088b208 (patch) | |
| tree | d9abcf526baee0100672851e0a8894c19e762a39 /arch/x86/kernel/irq_64.c | |
| parent | 68f30fbee19cc67849b9fa8e153ede70758afe81 (diff) | |
| parent | 90a4c0f51e8e44111a926be6f4c87af3938a79c3 (diff) | |
Merge remote-tracking branch 'linus/master' into x86/urgent
Diffstat (limited to 'arch/x86/kernel/irq_64.c')
| -rw-r--r-- | arch/x86/kernel/irq_64.c | 35 |
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 } |