diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 964d0446dae9..4bf6e64f94e0 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -1386,7 +1386,7 @@ static int tagged_addr_ctrl_get(struct task_struct *target,
 {
 	long ctrl = get_tagged_addr_ctrl(target);
 
-	if (IS_ERR_VALUE(ctrl))
+	if (WARN_ON_ONCE(IS_ERR_VALUE(ctrl)))
 		return ctrl;
 
 	return membuf_write(&to, &ctrl, sizeof(ctrl));
@@ -1400,6 +1400,10 @@ static int tagged_addr_ctrl_set(struct task_struct *target, const struct
 	int ret;
 	long ctrl;
 
+	ctrl = get_tagged_addr_ctrl(target);
+	if (WARN_ON_ONCE(IS_ERR_VALUE(ctrl)))
+		return ctrl;
+
 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl, 0, -1);
 	if (ret)
 		return ret;