From: Waiman Long Date: Sat, 21 Feb 2026 18:54:11 +0000 (-0500) Subject: cgroup/cpuset: Fix incorrect change to effective_xcpus in partition_xcpus_del() X-Git-Tag: v7.0-rc3~46^2~8 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f9a1767ce3a34bc33c3d33473f65dc13a380e379;p=thirdparty%2Fkernel%2Flinux.git cgroup/cpuset: Fix incorrect change to effective_xcpus in partition_xcpus_del() The effective_xcpus of a cpuset can contain offline CPUs. In partition_xcpus_del(), the xcpus parameter is incorrectly used as a temporary cpumask to mask out offline CPUs. As xcpus can be the effective_xcpus of a cpuset, this can result in unexpected changes in that cpumask. Fix this problem by not making any changes to the xcpus parameter. Fixes: 11e5f407b64a ("cgroup/cpuset: Keep track of CPUs in isolated partitions") Reviewed-by: Chen Ridong Signed-off-by: Waiman Long Signed-off-by: Tejun Heo --- diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index c43efef7df71..a366ef84f982 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -1221,8 +1221,8 @@ static void partition_xcpus_del(int old_prs, struct cpuset *parent, isolated_cpus_update(old_prs, parent->partition_root_state, xcpus); - cpumask_and(xcpus, xcpus, cpu_active_mask); cpumask_or(parent->effective_cpus, parent->effective_cpus, xcpus); + cpumask_and(parent->effective_cpus, parent->effective_cpus, cpu_active_mask); } /*