From: Scott Wood Date: Sat, 27 Jul 2019 00:56:32 -0500 Subject: [PATCH] sched: __set_cpus_allowed_ptr(): Check cpus_mask, not cpus_ptr Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.4/older/patches-5.4.13-rt7.tar.xz 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 Signed-off-by: Sebastian Andrzej Siewior --- kernel/sched/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1680,7 +1680,7 @@ static int __set_cpus_allowed_ptr(struct 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);