* [PATCH] sched: Do not use smp_processor_id() with preempt enabled in smpboot_thread_fn
@ 2016-09-13 6:27 Con Kolivas
2016-09-22 11:58 ` [tip:sched/core] sched/core: Do not use smp_processor_id() with preempt enabled in smpboot_thread_fn() tip-bot for Con Kolivas
0 siblings, 1 reply; 2+ messages in thread
From: Con Kolivas @ 2016-09-13 6:27 UTC (permalink / raw)
To: linux-kernel; +Cc: Peter Zijlstra, Alfred Chen, Ingo Molnar
We should not be using smp_processor_id() with preempt enabled.
Bug identified and fix provided by Alfred Chen.
Signed-off-by: Con Kolivas <kernel@kolivas.org>
---
kernel/smpboot.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Index: linux-4.7.3-ck3/kernel/smpboot.c
===================================================================
--- linux-4.7.3-ck3.orig/kernel/smpboot.c 2016-05-16 08:43:13.000000000 +1000
+++ linux-4.7.3-ck3/kernel/smpboot.c 2016-09-13 16:17:33.535655129 +1000
@@ -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;
^ permalink raw reply [flat|nested] 2+ messages in thread
* [tip:sched/core] sched/core: Do not use smp_processor_id() with preempt enabled in smpboot_thread_fn()
2016-09-13 6:27 [PATCH] sched: Do not use smp_processor_id() with preempt enabled in smpboot_thread_fn Con Kolivas
@ 2016-09-22 11:58 ` tip-bot for Con Kolivas
0 siblings, 0 replies; 2+ messages in thread
From: tip-bot for Con Kolivas @ 2016-09-22 11:58 UTC (permalink / raw)
To: linux-tip-commits
Cc: tglx, linux-kernel, mingo, hpa, peterz, kernel, cchalpha
Commit-ID: 4fa5cd5245b627db88c9ca08ae442373b02596b4
Gitweb: http://git.kernel.org/tip/4fa5cd5245b627db88c9ca08ae442373b02596b4
Author: Con Kolivas <kernel@kolivas.org>
AuthorDate: Tue, 13 Sep 2016 16:27:05 +1000
Committer: Ingo Molnar <mingo@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 <cchalpha@gmail.com>
Signed-off-by: Con Kolivas <kernel@kolivas.org>
Cc: Alfred Chen <cchalpha@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/2042051.3vvUWIM0vs@hex
Signed-off-by: Ingo Molnar <mingo@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;
^ permalink raw reply related [flat|nested] 2+ messages in thread
end of thread, other threads:[~2016-09-22 11:59 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-09-13 6:27 [PATCH] sched: Do not use smp_processor_id() with preempt enabled in smpboot_thread_fn Con Kolivas
2016-09-22 11:58 ` [tip:sched/core] sched/core: Do not use smp_processor_id() with preempt enabled in smpboot_thread_fn() tip-bot for Con Kolivas
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).