path: root/kernel/time
diff options
authorThomas Gleixner <tglx@linutronix.de>2013-05-03 15:02:50 +0200
committerThomas Gleixner <tglx@linutronix.de>2013-05-12 12:20:09 +0200
commit4b0c0f294f60abcdd20994a8341a95c8ac5eeb96 (patch)
treecdfb352f5cf66f5e5bb79fa9a975aabd891e1f62 /kernel/time
parentfbd44a607a1a5019bc32c3615cead8c5ee8f89c9 (diff)
tick: Cleanup NOHZ per cpu data on cpu down
Prarit reported a crash on CPU offline/online. The reason is that on CPU down the NOHZ related per cpu data of the dead cpu is not cleaned up. If at cpu online an interrupt happens before the per cpu tick device is registered the irq_enter() check potentially sees stale data and dereferences a NULL pointer. Cleanup the data after the cpu is dead. Reported-by: Prarit Bhargava <prarit@redhat.com> Cc: stable@vger.kernel.org Cc: Mike Galbraith <bitbucket@online.de> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305031451561.2886@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/time')
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 225f8bf1909..0eed1db2d79 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -904,7 +904,7 @@ void tick_cancel_sched_timer(int cpu)
# endif
- ts->nohz_mode = NOHZ_MODE_INACTIVE;
+ memset(ts, 0, sizeof(*ts));