kernel/watchdog.c: fix race between proc_watchdog_thresh() and watchdog_timer_fn()
Theoretically it is possible that the watchdog timer expires right at the time when a user sets 'watchdog_thresh' to zero (note: this disables the lockup detectors). In this scenario, the is_softlockup() function - which is called by the timer - could produce a false positive. Fix this by checking the current value of 'watchdog_thresh'. Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com> Acked-by: Don Zickus <dzickus@redhat.com> Reviewed-by: Aaron Tomlin <atomlin@redhat.com> Cc: Ulrich Obergfell <uobergfe@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:
parent
a2a45b85ec
commit
39d2da2161
1 changed files with 1 additions and 1 deletions
|
@ -289,7 +289,7 @@ static int is_softlockup(unsigned long touch_ts)
|
|||
{
|
||||
unsigned long now = get_timestamp();
|
||||
|
||||
if (watchdog_enabled & SOFT_WATCHDOG_ENABLED) {
|
||||
if ((watchdog_enabled & SOFT_WATCHDOG_ENABLED) && watchdog_thresh){
|
||||
/* Warn about unreasonable delays. */
|
||||
if (time_after(now, touch_ts + get_softlockup_thresh()))
|
||||
return now - touch_ts;
|
||||
|
|
Loading…
Reference in a new issue