diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 24ece85fd3b1..f7ad5651c93d 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1656,9 +1656,9 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd,
 		if (nocpu)
 			return PERR_NOCPUS;
 
-		cpumask_copy(tmp->delmask, xcpus);
-		deleting = true;
-		subparts_delta++;
+		deleting = cpumask_and(tmp->delmask, xcpus, parent->effective_xcpus);
+		if (deleting)
+			subparts_delta++;
 		new_prs = (cmd == partcmd_enable) ? PRS_ROOT : PRS_ISOLATED;
 	} else if (cmd == partcmd_disable) {
 		/*