diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c
index f86ee15be7cb..b685f45b4fd0 100644
--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -10380,11 +10380,9 @@ static int __init scx_init(void)
 	/*
 	 * cid-form must end exactly at @priv - validate_ops() skips
 	 * cpu_acquire/cpu_release for cid-form because reading those fields
-	 * past the BPF allocation would be UB. offsetofend() on both sides
-	 * instead of sizeof() on sched_ext_ops_cid to sidestep trailing
-	 * struct padding (e.g. 32-bit PPC tail-pads ops_cid past @priv).
+	 * past the BPF allocation would be UB.
 	 */
-	BUILD_BUG_ON(offsetofend(struct sched_ext_ops_cid, priv) !=
+	BUILD_BUG_ON(offsetof(struct sched_ext_ops_cid, __end) !=
 		     offsetofend(struct sched_ext_ops, priv));
 #undef CID_OFFSET_MATCH
 
diff --git a/kernel/sched/ext_internal.h b/kernel/sched/ext_internal.h
index 0ed79bd891c7..cd33984cffcf 100644
--- a/kernel/sched/ext_internal.h
+++ b/kernel/sched/ext_internal.h
@@ -938,6 +938,9 @@ struct sched_ext_ops_cid {
 
 	/* internal use only, must be NULL */
 	void __rcu *priv;
+
+	/* layout end anchor for the BUILD_BUG_ON in scx_init(); keep last */
+	char __end[0];
 };
 
 enum scx_opi {