From 888cafa05c94bccef4d7ceba7228dda7ae06f2fc Mon Sep 17 00:00:00 2001 From: Xiaotian Feng Date: Thu, 7 Jan 2010 11:22:44 +0800 Subject: [PATCH] clockevent: Don't remove broadcast device when cpu is dead commit ea9d8e3f45404d411c00ae67b45cc35c58265bb7 upstream. Marc reported that the BUG_ON in clockevents_notify() triggers on his system. This happens because the kernel tries to remove an active clock event device (used for broadcasting) from the device list. The handling of devices which can be used as per cpu device and as a global broadcast device is suboptimal. The simplest solution for now (and for stable) is to check whether the device is used as global broadcast device, but this needs to be revisited. [ tglx: restored the cpuweight check and massaged the changelog ] Reported-by: Marc Dionne Tested-by: Marc Dionne Signed-off-by: Xiaotian Feng LKML-Reference: <1262834564-13033-1-git-send-email-dfeng@redhat.com> Signed-off-by: Thomas Gleixner Acked-by: Jeff Mahoney Signed-off-by: Greg Kroah-Hartman --- kernel/time/clockevents.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 9484be456d69..0d809ae02d60 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -20,6 +20,8 @@ #include #include +#include "tick-internal.h" + /* The registered clock event devices */ static LIST_HEAD(clockevent_devices); static LIST_HEAD(clockevents_released); @@ -258,7 +260,8 @@ 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) { + cpumask_weight(dev->cpumask) == 1 && + !tick_is_broadcast_device(dev)) { BUG_ON(dev->mode != CLOCK_EVT_MODE_UNUSED); list_del(&dev->list); } -- 2.39.5