| From 1cc216bd8f60c579b2358826d01722bf8c03fa79 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Wed, 17 Jun 2020 14:17:42 +0200 |
| Subject: sched/core: Check cpus_mask, not cpus_ptr in |
| __set_cpus_allowed_ptr(), to fix mask corruption |
| |
| From: Scott Wood <swood@redhat.com> |
| |
| [ Upstream commit fd844ba9ae59b51e34e77105d79f8eca780b3bd6 ] |
| |
| This function is concerned with the long-term CPU mask, not the |
| transitory mask the task might have while migrate disabled. Before |
| this patch, if a task was migrate-disabled at the time |
| __set_cpus_allowed_ptr() was called, and the new mask happened to be |
| equal to the CPU that the task was running on, then the mask update |
| would be lost. |
| |
| Signed-off-by: Scott Wood <swood@redhat.com> |
| Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
| Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> |
| Signed-off-by: Ingo Molnar <mingo@kernel.org> |
| Link: https://lkml.kernel.org/r/20200617121742.cpxppyi7twxmpin7@linutronix.de |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| kernel/sched/core.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| diff --git a/kernel/sched/core.c b/kernel/sched/core.c |
| index 7238ef445dafb..8b3e99d095ae0 100644 |
| --- a/kernel/sched/core.c |
| +++ b/kernel/sched/core.c |
| @@ -1649,7 +1649,7 @@ static int __set_cpus_allowed_ptr(struct task_struct *p, |
| goto out; |
| } |
| |
| - if (cpumask_equal(p->cpus_ptr, new_mask)) |
| + if (cpumask_equal(&p->cpus_mask, new_mask)) |
| goto out; |
| |
| dest_cpu = cpumask_any_and(cpu_valid_mask, new_mask); |
| -- |
| 2.25.1 |
| |
