diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c
index b050641b5139..bb0140afed66 100644
--- a/arch/arm64/mm/mmap.c
+++ b/arch/arm64/mm/mmap.c
@@ -43,7 +43,7 @@ unsigned long arch_mmap_rnd(void)
 	unsigned long rnd;
 
 #ifdef CONFIG_COMPAT
-	if (test_thread_flag(TIF_32BIT))
+	if (is_compat_task())
 		rnd = get_random_long() & ((1UL << mmap_rnd_compat_bits) - 1);
 	else
 #endif