[PATCH v5 03/15] mm/kasan: mm/kasan: move kasan= code to common place

Baoquan He
2026-02-25T08:15:33Z

This allows generic and sw_tags to be set in kernel cmdline too.

Signed-off-by: Baoquan He <bhe@redhat.com>
---
include/linux/kasan-enabled.h | 2 ++
mm/kasan/common.c | 21 +++++++++++++++++++++
mm/kasan/hw_tags.c | 18 ------------------
3 files changed, 23 insertions(+), 18 deletions(-)

diff --git a/include/linux/kasan-enabled.h b/include/linux/kasan-enabled.h
index 9eca967d8526..b7cb906825ca 100644
--- a/include/linux/kasan-enabled.h
+++ b/include/linux/kasan-enabled.h
@@ -35,6 +35,8 @@ static inline void kasan_enable(void) {}
#endif /* CONFIG_ARCH_DEFER_KASAN || CONFIG_KASAN_HW_TAGS */

#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 b7d05c2a6d93..0d788a468e96 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -42,6 +42,27 @@ 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 */
+static int __init early_kasan_flag(char *arg)
+{
+ if (!arg)
+ return -EINVAL;
+
+ if (!strcmp(arg, "off"))
+ kasan_arg_disabled = true;
+ else if (!strcmp(arg, "on"))
+ kasan_arg_disabled = false;
+ else
+ return -EINVAL;
+
+ return 0;
+}
+early_param("kasan", early_kasan_flag);
+#endif
+
struct slab *kasan_addr_to_slab(const void *addr)
{
if (virt_addr_valid(addr))
diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c
index 26a69f0d822c..9602ea4861e2 100644
--- a/mm/kasan/hw_tags.c
+++ b/mm/kasan/hw_tags.c
@@ -35,7 +35,6 @@ enum kasan_arg_vmalloc {
KASAN_ARG_VMALLOC_ON,
};

-bool kasan_arg_disabled __ro_after_init;
static enum kasan_arg_mode kasan_arg_mode __ro_after_init;
static enum kasan_arg_vmalloc kasan_arg_vmalloc __initdata;

@@ -75,23 +74,6 @@ unsigned int kasan_page_alloc_sample_order = PAGE_ALLOC_SAMPLE_ORDER_DEFAULT;

DEFINE_PER_CPU(long, kasan_page_alloc_skip);

-/* kasan=off/on */
-static int __init early_kasan_flag(char *arg)
-{
- if (!arg)
- return -EINVAL;
-
- if (!strcmp(arg, "off"))
- kasan_arg_disabled = true;
- else if (!strcmp(arg, "on"))
- kasan_arg_disabled = false;
- else
- return -EINVAL;
-
- return 0;
-}
-early_param("kasan", early_kasan_flag);
-
/* kasan.mode=sync/async/asymm */
static int __init early_kasan_mode(char *arg)
{