Re: [PATCH] clockevent: don't remove broadcast device when cpu isdead

From: Xiaotian Feng
Date: Mon Jan 11 2010 - 21:27:18 EST


Any comments on the patch? Marc confirmed this patch also fixed his hang at suspend/resume stage. Thanks.

(Cc'ed stable@xxxxxxxxxx)


On 01/07/2010 11:22 AM, Xiaotian Feng wrote:
Marc reported BUG during shutdown, after debugging, kernel is trying
to remove a broadcast device which mode is CLOCK_EVT_MODE_ONESHOT.

The root cause for this bug is that in clockevents_notify,
"cpumask_weight(dev->cpumask) == 1" is always true even if dev is a
broadcast device. We need to use tick_is_broadcast_device to check
if it is a broadcast device.

Reported-by: Marc Dionne<marc.c.dionne@xxxxxxxxx>
Tested-by: Marc Dionne<marc.c.dionne@xxxxxxxxx>
Signed-off-by: Xiaotian Feng<dfeng@xxxxxxxxxx>
Cc: Thomas Gleixner<tglx@xxxxxxxxxxxxx>
Cc: Magnus Damm<damm@xxxxxxxxxx>
Cc: H Hartley Sweeten<hsweeten@xxxxxxxxxxxxxxxxxxx>
kernel/time/clockevents.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 6f740d9..0223d83 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -259,7 +259,7 @@ void clockevents_notify(unsigned long reason, void *arg)
cpu = *((int *)arg);
list_for_each_entry_safe(dev, tmp,&clockevent_devices, list) {
if (cpumask_test_cpu(cpu, dev->cpumask)&&
- cpumask_weight(dev->cpumask) == 1) {
+ !tick_is_broadcast_device(dev)) {

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at