| Message ID | 20210217165651.8563-1-mathieu.desnoyers@efficios.com |
|---|---|
| State | Accepted |
| Commit | ce29ddc47b91f97e7f69a0fb7cbb5845f52a9825 |
| Headers | show |
| Series | sched/membarrier: fix missing local execution of ipi_sync_rq_state() | expand |
diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c index 08ae45ad9261..f311bf85d211 100644 --- a/kernel/sched/membarrier.c +++ b/kernel/sched/membarrier.c @@ -471,9 +471,7 @@ static int sync_runqueues_membarrier_state(struct mm_struct *mm) } rcu_read_unlock(); - preempt_disable(); - smp_call_function_many(tmpmask, ipi_sync_rq_state, mm, 1); - preempt_enable(); + on_each_cpu_mask(tmpmask, ipi_sync_rq_state, mm, true); free_cpumask_var(tmpmask); cpus_read_unlock();
The function sync_runqueues_membarrier_state() should copy the membarrier state from the @mm received as parameter to each runqueue currently running tasks using that mm. However, the use of smp_call_function_many() skips the current runqueue, which is unintended. Replace by a call to on_each_cpu_mask(). Fixes: 227a4aadc75b ("sched/membarrier: Fix p->mm->membarrier_state racy load") Link: https://lore.kernel.org/r/74F1E842-4A84-47BF-B6C2-5407DFDD4A4A@gmail.com Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reported-by: Nadav Amit <nadav.amit@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: stable@vger.kernel.org # 5.4.x+ --- kernel/sched/membarrier.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)