diff --git a/arch/powerpc/perf/callchain.h b/arch/powerpc/perf/callchain.h
index ae24d4a00da6..d6fa6e25234f 100644
--- a/arch/powerpc/perf/callchain.h
+++ b/arch/powerpc/perf/callchain.h
@@ -33,7 +33,7 @@ static inline int __read_user_stack(const void __user *ptr, void *ret,
 
 	rc = copy_from_user_nofault(ret, ptr, size);
 
-	if (IS_ENABLED(CONFIG_PPC64) && rc)
+	if (IS_ENABLED(CONFIG_PPC64) && !radix_enabled() && rc)
 		return read_user_stack_slow(ptr, ret, size);
 
 	return rc;
diff --git a/arch/powerpc/perf/callchain_64.c b/arch/powerpc/perf/callchain_64.c
index fed90e827f3a..0777b04a0c56 100644
--- a/arch/powerpc/perf/callchain_64.c
+++ b/arch/powerpc/perf/callchain_64.c
@@ -21,7 +21,8 @@
 /*
  * On 64-bit we don't want to invoke hash_page on user addresses from
  * interrupt context, so if the access faults, we read the page tables
- * to find which page (if any) is mapped and access it directly.
+ * to find which page (if any) is mapped and access it directly. Radix
+ * has no need for this so it doesn't use read_user_stack_slow.
  */
 int read_user_stack_slow(const void __user *ptr, void *buf, int nb)
 {