diff options
| author | Don Zickus <dzickus@redhat.com> | 2015-11-05 18:44:44 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-11-05 19:34:48 -0800 |
| commit | ac1f591249d95372f3a5ab3828d4af5dfbf5efd3 (patch) | |
| tree | 39dfce1a0fc12de79689cd97e2876ddf777c8cab | |
| parent | 55537871ef666b4153fd1ef8782e4a13fee142cc (diff) | |
kernel/watchdog.c: add sysctl knob hardlockup_panic
The only way to enable a hardlockup to panic the machine is to set
'nmi_watchdog=panic' on the kernel command line.
This makes it awkward for end users and folks who want to run automate
tests (like myself).
Mimic the softlockup_panic knob and create a /proc/sys/kernel/hardlockup_panic
knob.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | Documentation/lockup-watchdogs.txt | 5 | ||||
| -rw-r--r-- | include/linux/sched.h | 1 | ||||
| -rw-r--r-- | kernel/sysctl.c | 11 | ||||
| -rw-r--r-- | kernel/watchdog.c | 2 |
4 files changed, 16 insertions, 3 deletions
diff --git a/Documentation/lockup-watchdogs.txt b/Documentation/lockup-watchdogs.txt index 22dd6af2e4bd..4a6e33e1af61 100644 --- a/Documentation/lockup-watchdogs.txt +++ b/Documentation/lockup-watchdogs.txt @@ -20,8 +20,9 @@ kernel mode for more than 10 seconds (see "Implementation" below for details), without letting other interrupts have a chance to run. Similarly to the softlockup case, the current stack trace is displayed upon detection and the system will stay locked up unless the default -behavior is changed, which can be done through a compile time knob, -"BOOTPARAM_HARDLOCKUP_PANIC", and a kernel parameter, "nmi_watchdog" +behavior is changed, which can be done through a sysctl, +'hardlockup_panic', a compile time knob, "BOOTPARAM_HARDLOCKUP_PANIC", +and a kernel parameter, "nmi_watchdog" (see "Documentation/kernel-parameters.txt" for details). The panic option can be used in combination with panic_timeout (this diff --git a/include/linux/sched.h b/include/linux/sched.h index c115d617739d..5423b9c82fee 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -384,6 +384,7 @@ extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos); extern unsigned int softlockup_panic; +extern unsigned int hardlockup_panic; void lockup_detector_init(void); #else static inline void touch_softlockup_watchdog(void) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 1a5faa3e1521..dc6858d6639e 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -888,6 +888,17 @@ static struct ctl_table kern_table[] = { .extra1 = &zero, .extra2 = &one, }, +#ifdef CONFIG_HARDLOCKUP_DETECTOR + { + .procname = "hardlockup_panic", + .data = &hardlockup_panic, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, + }, +#endif #ifdef CONFIG_SMP { .procname = "softlockup_all_cpu_backtrace", diff --git a/kernel/watchdog.c b/kernel/watchdog.c index f6b32b8cbffe..0a23125369f1 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -112,7 +112,7 @@ static unsigned long soft_lockup_nmi_warn; * Should we panic when a soft-lockup or hard-lockup occurs: */ #ifdef CONFIG_HARDLOCKUP_DETECTOR -static int hardlockup_panic = +unsigned int __read_mostly hardlockup_panic = CONFIG_BOOTPARAM_HARDLOCKUP_PANIC_VALUE; static unsigned long hardlockup_allcpu_dumped; /* |