Subject: [PATCH v5 04/15] mm/kasan: make kasan=on|off take effect for all three modes

From: Baoquan He <[email-masked]>
Date: Wed, 25 Feb 2026 16:14:01 +0800

Now everything is ready, setting kasan=off can disable kasan for all
three modes.

Signed-off-by: Baoquan He <[email-masked]>
---
 include/linux/kasan-enabled.h | 12 +++++-------
 mm/kasan/common.c             |  4 ----
 2 files changed, 5 insertions(+), 11 deletions(-)

diff --git a/include/linux/kasan-enabled.h b/include/linux/kasan-enabled.h
index b7cb906825ca..cec21a08446e 100644
--- a/include/linux/kasan-enabled.h
+++ b/include/linux/kasan-enabled.h
@@ -4,10 +4,11 @@
 
 #include <linux/static_key.h>
 
-#if defined(CONFIG_ARCH_DEFER_KASAN) || defined(CONFIG_KASAN_HW_TAGS)
+#ifdef CONFIG_KASAN
+extern bool kasan_arg_disabled;
+
 /*
  * Global runtime flag for KASAN modes that need runtime control.
- * Used by ARCH_DEFER_KASAN architectures and HW_TAGS mode.
  */
 DECLARE_STATIC_KEY_FALSE(kasan_flag_enabled);
 
@@ -25,18 +26,15 @@ static inline void kasan_enable(void)
 	static_branch_enable(&kasan_flag_enabled);
 }
 #else
-/* For architectures that can enable KASAN early, use compile-time check. */
 static __always_inline bool kasan_enabled(void)
 {
-	return IS_ENABLED(CONFIG_KASAN);
+	return false;
 }
 
 static inline void kasan_enable(void) {}
-#endif /* CONFIG_ARCH_DEFER_KASAN || CONFIG_KASAN_HW_TAGS */
+#endif
 
 #ifdef CONFIG_KASAN_HW_TAGS
-extern bool kasan_arg_disabled;
-
 static inline bool kasan_hw_tags_enabled(void)
 {
 	return kasan_enabled();
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 0d788a468e96..fc6513fa5795 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -33,16 +33,13 @@
 #include "kasan.h"
 #include "../slab.h"
 
-#if defined(CONFIG_ARCH_DEFER_KASAN) || defined(CONFIG_KASAN_HW_TAGS)
 /*
  * Definition of the unified static key declared in kasan-enabled.h.
  * This provides consistent runtime enable/disable across KASAN modes.
  */
 DEFINE_STATIC_KEY_FALSE(kasan_flag_enabled);
 EXPORT_SYMBOL_GPL(kasan_flag_enabled);
-#endif
 
-#ifdef CONFIG_KASAN_HW_TAGS
 bool kasan_arg_disabled __ro_after_init;
 
 /* kasan=off/on */
@@ -61,7 +58,6 @@ static int __init early_kasan_flag(char *arg)
 	return 0;
 }
 early_param("kasan", early_kasan_flag);
-#endif
 
 struct slab *kasan_addr_to_slab(const void *addr)
 {
-- 
2.52.0