sched: Sched_rt_periodic_timer vs cpu hotplug
authorPeter Zijlstra <a.p.zijlstra@chello.nl>
Mon, 16 Nov 2009 09:28:09 +0000 (10:28 +0100)
committerIngo Molnar <mingo@elte.hu>
Mon, 16 Nov 2009 09:46:27 +0000 (10:46 +0100)
commit047106adcc85e3023da210143a6ab8a55df9e0fc
treedd92c3c65229622bed4b27c60f7d617c9dbf1a2a
parent498657a478c60be092208422fefa9c7b248729c2
sched: Sched_rt_periodic_timer vs cpu hotplug

Heiko reported a case where a timer interrupt managed to
reference a root_domain structure that was already freed by a
concurrent hot-un-plug operation.

Solve this like the regular sched_domain stuff is also
synchronized, by adding a synchronize_sched() stmt to the free
path, this ensures that a root_domain stays present for any
atomic section that could have observed it.

Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Gregory Haskins <ghaskins@novell.com>
Cc: Siddha Suresh B <suresh.b.siddha@intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
LKML-Reference: <1258363873.26714.83.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kernel/sched.c