Add early-boot-safety check to cond_resched()
Just to be safe, we should not trigger a conditional reschedule during
the early boot sequence. We've historically done some questionable
early on, and the safety warnings in __might_sleep() are generally
turned off during that period, so there might be problems lurking.
This affects CONFIG_PREEMPT_VOLUNTARY, which takes over might_sleep() to
cause a voluntary conditional reschedule.
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/sched.c b/kernel/sched.c
index 12d291b..3454bb8 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4028,6 +4028,8 @@
*/
if (unlikely(preempt_count()))
return;
+ if (unlikely(system_state != SYSTEM_RUNNING))
+ return;
do {
add_preempt_count(PREEMPT_ACTIVE);
schedule();