diff options
Diffstat (limited to 'kernel/panic.c')
| -rw-r--r-- | kernel/panic.c | 53 |
1 files changed, 48 insertions, 5 deletions
diff --git a/kernel/panic.c b/kernel/panic.c index da323209f583..463c9295bc28 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -25,6 +25,7 @@ #include <linux/kexec.h> #include <linux/panic_notifier.h> #include <linux/sched.h> +#include <linux/string_helpers.h> #include <linux/sysrq.h> #include <linux/init.h> #include <linux/nmi.h> @@ -32,6 +33,7 @@ #include <linux/bug.h> #include <linux/ratelimit.h> #include <linux/debugfs.h> +#include <linux/sysfs.h> #include <trace/events/error_report.h> #include <asm/sections.h> @@ -58,6 +60,7 @@ bool crash_kexec_post_notifiers; int panic_on_warn __read_mostly; unsigned long panic_on_taint; bool panic_on_taint_nousertaint = false; +static unsigned int warn_limit __read_mostly; int panic_timeout = CONFIG_PANIC_TIMEOUT; EXPORT_SYMBOL_GPL(panic_timeout); @@ -75,8 +78,9 @@ ATOMIC_NOTIFIER_HEAD(panic_notifier_list); EXPORT_SYMBOL(panic_notifier_list); -#if defined(CONFIG_SMP) && defined(CONFIG_SYSCTL) +#ifdef CONFIG_SYSCTL static struct ctl_table kern_panic_table[] = { +#ifdef CONFIG_SMP { .procname = "oops_all_cpu_backtrace", .data = &sysctl_oops_all_cpu_backtrace, @@ -86,6 +90,14 @@ static struct ctl_table kern_panic_table[] = { .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_ONE, }, +#endif + { + .procname = "warn_limit", + .data = &warn_limit, + .maxlen = sizeof(warn_limit), + .mode = 0644, + .proc_handler = proc_douintvec, + }, { } }; @@ -97,6 +109,25 @@ static __init int kernel_panic_sysctls_init(void) late_initcall(kernel_panic_sysctls_init); #endif +static atomic_t warn_count = ATOMIC_INIT(0); + +#ifdef CONFIG_SYSFS +static ssize_t warn_count_show(struct kobject *kobj, struct kobj_attribute *attr, + char *page) +{ + return sysfs_emit(page, "%d\n", atomic_read(&warn_count)); +} + +static struct kobj_attribute warn_count_attr = __ATTR_RO(warn_count); + +static __init int kernel_panic_sysfs_init(void) +{ + sysfs_add_file_to_group(kernel_kobj, &warn_count_attr.attr, NULL); + return 0; +} +late_initcall(kernel_panic_sysfs_init); +#endif + static long no_blink(int state) { return 0; @@ -199,6 +230,19 @@ static void panic_print_sys_info(bool console_flush) ftrace_dump(DUMP_ALL); } +void check_panic_on_warn(const char *origin) +{ + unsigned int limit; + + if (panic_on_warn) + panic("%s: panic_on_warn set ...\n", origin); + + limit = READ_ONCE(warn_limit); + if (atomic_inc_return(&warn_count) >= limit && limit) + panic("%s: system warned too often (kernel.warn_limit is %d)", + origin, limit); +} + /** * panic - halt the system * @fmt: The text string to print @@ -617,8 +661,7 @@ void __warn(const char *file, int line, void *caller, unsigned taint, if (regs) show_regs(regs); - if (panic_on_warn) - panic("panic_on_warn set ...\n"); + check_panic_on_warn("kernel"); if (!regs) dump_stack(); @@ -744,8 +787,8 @@ static int __init panic_on_taint_setup(char *s) if (s && !strcmp(s, "nousertaint")) panic_on_taint_nousertaint = true; - pr_info("panic_on_taint: bitmask=0x%lx nousertaint_mode=%sabled\n", - panic_on_taint, panic_on_taint_nousertaint ? "en" : "dis"); + pr_info("panic_on_taint: bitmask=0x%lx nousertaint_mode=%s\n", + panic_on_taint, str_enabled_disabled(panic_on_taint_nousertaint)); return 0; } |