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sched/membarrier: fix missing local execution of ipi_sync_rq_state()

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commit ce29ddc47b91f97e7f69a0fb7cbb5845f52a9825 upstream.

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: 227a4aadc7 ("sched/membarrier: Fix p->mm->membarrier_state racy load")
Reported-by: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org # 5.4.x+
Link: https://lore.kernel.org/r/74F1E842-4A84-47BF-B6C2-5407DFDD4A4A@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mathieu Desnoyers 2021-02-17 11:56:51 -05:00 committed by Greg Kroah-Hartman
parent 2306580a95
commit 907f7f2cf0
1 changed files with 1 additions and 3 deletions
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4
kernel/sched/membarrier.c
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@ -265,9 +265,7 @@ static int sync_runqueues_membarrier_state(struct mm_struct *mm)
} }
rcu_read_unlock(); rcu_read_unlock();
preempt_disable(); on_each_cpu_mask(tmpmask, ipi_sync_rq_state, mm, true);
smp_call_function_many(tmpmask, ipi_sync_rq_state, mm, 1);
preempt_enable();
free_cpumask_var(tmpmask); free_cpumask_var(tmpmask);
cpus_read_unlock(); cpus_read_unlock();