From: Guopeng Zhang Date: Sat, 9 May 2026 10:20:30 +0000 (+0800) Subject: cgroup/cpuset: Reset DL migration state on can_attach() failure X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=4a39eda5fdd867fc39f3c039714dd432cee00268;p=thirdparty%2Fkernel%2Flinux.git cgroup/cpuset: Reset DL migration state on can_attach() failure cpuset_can_attach() accumulates temporary SCHED_DEADLINE migration state in the destination cpuset while walking the taskset. If a later task_can_attach() or security_task_setscheduler() check fails, cgroup_migrate_execute() treats cpuset as the failing subsystem and does not call cpuset_cancel_attach() for it. The partially accumulated state is then left behind and can be consumed by a later attach, corrupting cpuset DL task accounting and pending DL bandwidth accounting. Reset the pending DL migration state from the common error exit when ret is non-zero. Successful can_attach() keeps the state for cpuset_attach() or cpuset_cancel_attach(). Fixes: 2ef269ef1ac0 ("cgroup/cpuset: Free DL BW in case can_attach() fails") Cc: stable@vger.kernel.org # v6.10+ Signed-off-by: Guopeng Zhang Signed-off-by: Tejun Heo Reviewed-by: Chen Ridong Reviewed-by: Waiman Long --- diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index a48901a0416a..3fbf6e7f68c3 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -3050,16 +3050,13 @@ static int cpuset_can_attach(struct cgroup_taskset *tset) int cpu = cpumask_any_and(cpu_active_mask, cs->effective_cpus); if (unlikely(cpu >= nr_cpu_ids)) { - reset_migrate_dl_data(cs); ret = -EINVAL; goto out_unlock; } ret = dl_bw_alloc(cpu, cs->sum_migrate_dl_bw); - if (ret) { - reset_migrate_dl_data(cs); + if (ret) goto out_unlock; - } cs->dl_bw_cpu = cpu; } @@ -3070,7 +3067,10 @@ out_success: * changes which zero cpus/mems_allowed. */ cs->attach_in_progress++; + out_unlock: + if (ret) + reset_migrate_dl_data(cs); mutex_unlock(&cpuset_mutex); return ret; }