Merge tag 'cgroup-for-6.15-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

d471045e · Linus Torvalds <[email protected]> · 2025-05-12 17:58:57 -07:00

Pull cgroup fix from Tejun Heo:
 "One low-risk patch to fix a cpuset bug where it over-eagerly tries to
  modify CPU affinity of kernel threads"

* tag 'cgroup-for-6.15-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup/cpuset: Extend kthread_is_per_cpu() check to all PF_NO_SETAFFINITY tasks

Commit: d471045e757e941ca802bca3147aab45bf770754
Parents: 7a8bdc7f · 39b5ef79

Merge commit. Changes below are compared with the first parent: 7a8bdc7f.

Changes

1 files changed · +4 −2

File	Status	Add	Del	Content
kernel/cgroup/cpuset.c	modified	+4	−2	View file

kernel/cgroup/cpuset.c

View file

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 306b604..24b70ea 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1116,9 +1116,11 @@ void cpuset_update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus)
 
 		if (top_cs) {
 			/*
-			 * Percpu kthreads in top_cpuset are ignored
+			 * PF_NO_SETAFFINITY tasks are ignored.
+			 * All per cpu kthreads should have PF_NO_SETAFFINITY
+			 * flag set, see kthread_set_per_cpu().
 			 */
-			if (kthread_is_per_cpu(task))
+			if (task->flags & PF_NO_SETAFFINITY)
 				continue;
 			cpumask_andnot(new_cpus, possible_mask, subpartitions_cpus);
 		} else {