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Diffstat (limited to 'kernel/panic.c')
-rw-r--r--kernel/panic.c45
1 files changed, 42 insertions, 3 deletions
diff --git a/kernel/panic.c b/kernel/panic.c
index 75fe389e8814..326d91505f04 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -33,6 +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>
@@ -59,6 +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);
@@ -76,8 +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,
@@ -87,6 +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,
+ },
{ }
};
@@ -98,6 +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;
@@ -200,6 +230,16 @@ static void panic_print_sys_info(bool console_flush)
ftrace_dump(DUMP_ALL);
}
+void check_panic_on_warn(const char *origin)
+{
+ if (panic_on_warn)
+ panic("%s: panic_on_warn set ...\n", origin);
+
+ if (atomic_inc_return(&warn_count) >= READ_ONCE(warn_limit) && warn_limit)
+ panic("%s: system warned too often (kernel.warn_limit is %d)",
+ origin, warn_limit);
+}
+
/**
* panic - halt the system
* @fmt: The text string to print
@@ -618,8 +658,7 @@ 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();