Commit-ID: 4fa5cd5245b627db88c9ca08ae442373b02596b4 Gitweb: http://git.kernel.org/tip/4fa5cd5245b627db88c9ca08ae442373b02596b4 Author: Con Kolivas <ker...@kolivas.org> AuthorDate: Tue, 13 Sep 2016 16:27:05 +1000 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Thu, 22 Sep 2016 12:28:00 +0200
sched/core: Do not use smp_processor_id() with preempt enabled in smpboot_thread_fn() We should not be using smp_processor_id() with preempt enabled. Bug identified and fix provided by Alfred Chen. Reported-by: Alfred Chen <cchal...@gmail.com> Signed-off-by: Con Kolivas <ker...@kolivas.org> Cc: Alfred Chen <cchal...@gmail.com> Cc: Peter Zijlstra <pet...@infradead.org> Link: http://lkml.kernel.org/r/2042051.3vvUWIM0vs@hex Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/smpboot.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/smpboot.c b/kernel/smpboot.c index 13bc43d..fc0d8270 100644 --- a/kernel/smpboot.c +++ b/kernel/smpboot.c @@ -122,12 +122,12 @@ static int smpboot_thread_fn(void *data) if (kthread_should_park()) { __set_current_state(TASK_RUNNING); - preempt_enable(); if (ht->park && td->status == HP_THREAD_ACTIVE) { BUG_ON(td->cpu != smp_processor_id()); ht->park(td->cpu); td->status = HP_THREAD_PARKED; } + preempt_enable(); kthread_parkme(); /* We might have been woken for stop */ continue;
