Commit-ID: 99d84bf8c65a7a0dbc9e166ca0a58ed949ac4f37
Gitweb: https://git.kernel.org/tip/99d84bf8c65a7a0dbc9e166ca0a58ed949ac4f37
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Wed, 29 May 2019 20:36:37 +0000
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitDate: Thu, 8 Aug 2019 09:09:30 +0200
stop_machine: Fix stop_cpus_in_progress ordering
Make sure the entire for loop has stop_cpus_in_progress set.
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Aaron Lu <aaron.lwe@xxxxxxxxx>
Cc: Valentin Schneider <valentin.schneider@xxxxxxx>
Cc: mingo@xxxxxxxxxx
Cc: Phil Auld <pauld@xxxxxxxxxx>
Cc: Julien Desfossez <jdesfossez@xxxxxxxxxxxxxxxx>
Cc: Nishanth Aravamudan <naravamudan@xxxxxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/0fd8fd4b99b9b9aa88d8b2dff897f7fd0d88f72c.1559129225.git.vpillai@xxxxxxxxxxxxxxxx
---
kernel/stop_machine.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index b4f83f7bdf86..c7031a22aa7b 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -383,6 +383,7 @@ static bool queue_stop_cpus_work(const struct cpumask *cpumask,
*/
preempt_disable();
stop_cpus_in_progress = true;
+ barrier();
for_each_cpu(cpu, cpumask) {
work = &per_cpu(cpu_stopper.stop_work, cpu);
work->fn = fn;
@@ -391,6 +392,7 @@ static bool queue_stop_cpus_work(const struct cpumask *cpumask,
if (cpu_stop_queue_work(cpu, work))
queued = true;
}
+ barrier();
stop_cpus_in_progress = false;
preempt_enable();
|