path: root/kernel/watchdog.c
diff options
authorThomas Gleixner <tglx@linutronix.de>2012-12-04 18:59:34 +0100
committerThomas Gleixner <tglx@linutronix.de>2012-12-04 19:56:59 +0100
commit8d4516904b39507458bee8115793528e12b1d8dd (patch)
tree4afc56d198921b85f61918c2478cfc93fb2dc96e /kernel/watchdog.c
parentb69f0859dc8e633c5d8c06845811588fe17e68b3 (diff)
watchdog: Fix CPU hotplug regression
Norbert reported: "3.7-rc6 booted with nmi_watchdog=0 fails to suspend to RAM or offline CPUs. It's reproducable with a KVM guest and physical system." The reason is that commit bcd951cf(watchdog: Use hotplug thread infrastructure) missed to take this into account. So the cpu offline code gets stuck in the teardown function because it accesses non initialized data structures. Add a check for watchdog_enabled into that path to cure the issue. Reported-and-tested-by: Norbert Warmuth <nwarmuth@t-online.de> Tested-by: Joseph Salisbury <joseph.salisbury@canonical.com> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1211231033230.2701@ionos Link: http://bugs.launchpad.net/bugs/1079534 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/watchdog.c')
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index dd4b80a9f1a9..c8c21be11ab4 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -368,6 +368,9 @@ static void watchdog_disable(unsigned int cpu)
struct hrtimer *hrtimer = &__raw_get_cpu_var(watchdog_hrtimer);
+ if (!watchdog_enabled)
+ return;
watchdog_set_prio(SCHED_NORMAL, 0);
/* disable the perf event */