diff options
| -rw-r--r-- | Documentation/sysctl/kernel.txt | 14 | ||||
| -rw-r--r-- | arch/x86/kernel/irq_32.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/irq_64.c | 5 | ||||
| -rw-r--r-- | include/linux/kernel.h | 1 | ||||
| -rw-r--r-- | kernel/sysctl.c | 9 |
5 files changed, 31 insertions, 0 deletions
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index 1f2463671a1a..6d8cd8b2c30d 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -49,6 +49,7 @@ show up in /proc/sys/kernel: - panic - panic_on_oops - panic_on_unrecovered_nmi +- panic_on_stackoverflow - pid_max - powersave-nap [ PPC only ] - printk @@ -393,6 +394,19 @@ Controls the kernel's behaviour when an oops or BUG is encountered. ============================================================== +panic_on_stackoverflow: + +Controls the kernel's behavior when detecting the overflows of +kernel, IRQ and exception stacks except a user stack. +This file shows up if CONFIG_DEBUG_STACKOVERFLOW is enabled. + +0: try to continue operation. + +1: panic immediately. + +============================================================== + + pid_max: PID allocation wrap value. When the kernel's next PID value diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c index 72090705a656..e16e99ebd7ad 100644 --- a/arch/x86/kernel/irq_32.c +++ b/arch/x86/kernel/irq_32.c @@ -43,6 +43,8 @@ static void print_stack_overflow(void) { printk(KERN_WARNING "low stack detected by irq handler\n"); dump_stack(); + if (sysctl_panic_on_stackoverflow) + panic("low stack detected by irq handler - check messages\n"); } #else diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c index 928a7e909619..42552b0dce6a 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: * @@ -65,6 +67,9 @@ static inline void stack_overflow_check(struct pt_regs *regs) current->comm, curbase, regs->sp, irq_stack_top, irq_stack_bottom, estack_top, estack_bottom); + + if (sysctl_panic_on_stackoverflow) + panic("low stack detected by irq handler - check messages\n"); #endif } diff --git a/include/linux/kernel.h b/include/linux/kernel.h index e8b1597b5cf2..ff83683c0b9d 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -341,6 +341,7 @@ extern int panic_timeout; extern int panic_on_oops; extern int panic_on_unrecovered_nmi; extern int panic_on_io_nmi; +extern int sysctl_panic_on_stackoverflow; extern const char *print_tainted(void); extern void add_taint(unsigned flag); extern int test_taint(unsigned flag); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index ae2719643854..f487f257e05e 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -803,6 +803,15 @@ static struct ctl_table kern_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, +#ifdef CONFIG_DEBUG_STACKOVERFLOW + { + .procname = "panic_on_stackoverflow", + .data = &sysctl_panic_on_stackoverflow, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, +#endif { .procname = "bootloader_type", .data = &bootloader_type, |