From 1409f141ac719b994d2832911b1e9ec928943fc2 Mon Sep 17 00:00:00 2001 From: Hillf Danton Date: Wed, 27 Apr 2011 15:26:55 -0700 Subject: [PATCH] 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 Signed-off-by: Don Zickus Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/watchdog.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 140dce750450..14733d4d156b 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -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); -- 2.20.1