diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index cec7fe8059a1..13a64488c3d2 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4914,6 +4914,15 @@ long sched_getaffinity(pid_t pid, struct cpumask *mask)
 
 	raw_spin_lock_irqsave(&p->pi_lock, flags);
 	cpumask_and(mask, &p->cpus_allowed, cpu_active_mask);
+
+	/*
+	 * The userspace tasks are forbidden to run on
+	 * isolated CPUs. So exclude isolated CPUs from
+	 * the getaffinity.
+	 */
+	if (!(p->flags & PF_KTHREAD))
+		cpumask_andnot(mask, mask, cpu_isolated_mask);
+
 	raw_spin_unlock_irqrestore(&p->pi_lock, flags);
 
 out_unlock: