From: Valentin Schneider <[email protected]> migrate_disable(); set_cpus_allowed_ptr(current, {something excluding task_cpu(current)}); affine_move_task(); <-- never returns
Signed-off-by: Valentin Schneider <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Link: https://lkml.kernel.org/r/[email protected] --- kernel/sched/core.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2182,8 +2182,17 @@ static int __set_cpus_allowed_ptr(struct goto out; } - if (!(flags & SCA_MIGRATE_ENABLE) && cpumask_equal(&p->cpus_mask, new_mask)) - goto out; + if (!(flags & SCA_MIGRATE_ENABLE)) { + if (cpumask_equal(&p->cpus_mask, new_mask)) + goto out; + + if (WARN_ON_ONCE(p == current && + is_migration_disabled(p) && + !cpumask_test_cpu(task_cpu(p), new_mask))) { + ret = -EBUSY; + goto out; + } + } /* * Picking a ~random cpu helps in cases where we are changing affinity
