kernel/watchdog.c: disable nmi perf event in the error path of enabling watchdog

In corner cases where softlockup watchdog is not setup successfully, the
relevant nmi perf event for hardlockup watchdog could be disabled, then
the status of the underlying hardware remains unchanged.

Also, if the kthread doesn't start then the hrtimer won't run and the
hardlockup detector will falsely fire.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Hillf Danton 2011-04-27 15:26:55 -07:00 committed by Linus Torvalds
parent 534e3adbd2
commit 1409f141ac

View file

@ -430,9 +430,12 @@ static int watchdog_enable(int cpu)
p = kthread_create(watchdog, (void *)(unsigned long)cpu, "watchdog/%d", cpu);
if (IS_ERR(p)) {
printk(KERN_ERR "softlockup watchdog for %i failed\n", cpu);
if (!err)
if (!err) {
/* if hardlockup hasn't already set this */
err = PTR_ERR(p);
/* and disable the perf event */
watchdog_nmi_disable(cpu);
}
goto out;
}
kthread_bind(p, cpu);