[PATCH 0/2] kasan: cleanups for kasan_enabled() checks

[PATCH 0/2] kasan: cleanups for kasan_enabled() checks

[Sabyrzhan Tasbolatov]

This patch series is the continuation of [1] the previous discussion
related to the KASAN internal refactoring.

Here we remove kasan_enabled() checks which are duplicated by higher callers.
These checks deduplication are also related to the separate patch series [2].

[1] https://lore.kernel.org/all/CA+fCnZce3AR+pUesbDkKMtMJ+iR8eDrcjFTbVpAcwjBoZ=gJnQ@mail.gmail.com/
[2] https://lore.kernel.org/all/aNTfPjS2buXMI46D@MiWiFi-R3L-srv/

* Altered functions:

check_page_allocation
	Delete the check because callers have it already in __wrappers in
	include/linux/kasan.h:
		__kasan_kfree_large
		__kasan_mempool_poison_pages
		__kasan_mempool_poison_object

kasan_populate_vmalloc, kasan_release_vmalloc
	Add __wrappers in include/linux/kasan.h.
	They are called externally in mm/vmalloc.c.

__kasan_unpoison_vmalloc, __kasan_poison_vmalloc
	Delete checks because there're already kasan_enabled() checks
	in respective __wrappers in include/linux/kasan.h.

release_free_meta -- Delete the check because the higher caller path
	has it already. See the stack trace:

	__kasan_slab_free -- has the check already
	__kasan_mempool_poison_object -- has the check already
		poison_slab_object
			kasan_save_free_info
				release_free_meta
					kasan_enabled() -- Delete here

* Other mm/kasan/* functions with kasan_enabled()
	where callers are defined in internal mm/kasan/kasan.h:

mm/kasan/generic.c:
	kasan_check_range
		check_region_inline
	kasan_byte_accessible

mm/kasan/shadow.c:
	kasan_poison
	kasan_poison_last_granule

mm/kasan/kasan_test_c.c:
	kasan_suite_init

== Tests:

* ARCH=um defconfig (-e KASAN, selects ARCH_DEFER_KASAN)
	Compiled and run ./linux with no issue

* ARCH=powerpc ppc64le_defconfig (-e KASAN, selects ARCH_DEFER_KASAN)
	Compiled and run qemu-system-ppc64 with no issue

* ARCH=arm64 defconfig (-e KASAN_GENERIC) and KUnit tests:

[    4.065375] # kasan: pass:61 fail:1 skip:14 total:76
[    4.065529] # Totals: pass:61 fail:1 skip:14 total:76
[    4.065682] not ok 1 kasan

1 test is failing:

[    3.772739]     # kasan_strings: EXPECTATION FAILED at mm/kasan/kasan_test_c.c:1700
[    3.772739]     KASAN failure expected in "strscpy(ptr, src + KASAN_GRANULE_SIZE, KASAN_GRANULE_SIZE)", but none occurred

which is also reproducable in the main tree.

Sabyrzhan Tasbolatov (2):
  kasan: remove __kasan_save_free_info wrapper
  kasan: cleanup of kasan_enabled() checks

 include/linux/kasan.h | 20 ++++++++++++++++++--
 mm/kasan/common.c     |  3 ---
 mm/kasan/generic.c    |  5 +----
 mm/kasan/kasan.h      |  7 +------
 mm/kasan/shadow.c     | 20 ++++----------------
 mm/kasan/tags.c       |  2 +-
 6 files changed, 25 insertions(+), 32 deletions(-)

-- 
2.34.1

[PATCH 1/2] kasan: remove __kasan_save_free_info wrapper

[Sabyrzhan Tasbolatov]

We don't need a kasan_enabled() check in
kasan_save_free_info() at all. Both the higher level paths
(kasan_slab_free and kasan_mempool_poison_object) already contain this
check. Therefore, remove the __wrapper.

Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
Fixes: 1e338f4d99e6 ("kasan: introduce ARCH_DEFER_KASAN and unify static key across modes")
---
 mm/kasan/generic.c | 2 +-
 mm/kasan/kasan.h   | 7 +------
 mm/kasan/tags.c    | 2 +-
 3 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index b413c46b3e0..516b49accc4 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -573,7 +573,7 @@ void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags)
 	kasan_save_track(&alloc_meta->alloc_track, flags);
 }
 
-void __kasan_save_free_info(struct kmem_cache *cache, void *object)
+void kasan_save_free_info(struct kmem_cache *cache, void *object)
 {
 	struct kasan_free_meta *free_meta;
 
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index 07fa7375a84..fc9169a5476 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -399,12 +399,7 @@ void kasan_set_track(struct kasan_track *track, depot_stack_handle_t stack);
 void kasan_save_track(struct kasan_track *track, gfp_t flags);
 void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags);
 
-void __kasan_save_free_info(struct kmem_cache *cache, void *object);
-static inline void kasan_save_free_info(struct kmem_cache *cache, void *object)
-{
-	if (kasan_enabled())
-		__kasan_save_free_info(cache, object);
-}
+void kasan_save_free_info(struct kmem_cache *cache, void *object);
 
 #ifdef CONFIG_KASAN_GENERIC
 bool kasan_quarantine_put(struct kmem_cache *cache, void *object);
diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c
index b9f31293622..d65d48b85f9 100644
--- a/mm/kasan/tags.c
+++ b/mm/kasan/tags.c
@@ -142,7 +142,7 @@ void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags)
 	save_stack_info(cache, object, flags, false);
 }
 
-void __kasan_save_free_info(struct kmem_cache *cache, void *object)
+void kasan_save_free_info(struct kmem_cache *cache, void *object)
 {
 	save_stack_info(cache, object, 0, true);
 }
-- 
2.34.1

[PATCH 2/2] kasan: cleanup of kasan_enabled() checks

[Sabyrzhan Tasbolatov]

Deduplication of kasan_enabled() checks which are already used by callers.

* Altered functions:

check_page_allocation
	Delete the check because callers have it already in __wrappers in
	include/linux/kasan.h:
		__kasan_kfree_large
		__kasan_mempool_poison_pages
		__kasan_mempool_poison_object

kasan_populate_vmalloc, kasan_release_vmalloc
	Add __wrappers in include/linux/kasan.h.
	They are called externally in mm/vmalloc.c.

__kasan_unpoison_vmalloc, __kasan_poison_vmalloc
	Delete checks because there're already kasan_enabled() checks
	in respective __wrappers in include/linux/kasan.h.

release_free_meta -- Delete the check because the higher caller path
	has it already. See the stack trace:

	__kasan_slab_free -- has the check already
	__kasan_mempool_poison_object -- has the check already
		poison_slab_object
			kasan_save_free_info
				release_free_meta
					kasan_enabled() -- Delete here

Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
---
 include/linux/kasan.h | 20 ++++++++++++++++++--
 mm/kasan/common.c     |  3 ---
 mm/kasan/generic.c    |  3 ---
 mm/kasan/shadow.c     | 20 ++++----------------
 4 files changed, 22 insertions(+), 24 deletions(-)

diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index d12e1a5f5a9..f335c1d7b61 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -571,11 +571,27 @@ static inline void kasan_init_hw_tags(void) { }
 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 
 void kasan_populate_early_vm_area_shadow(void *start, unsigned long size);
-int kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask);
-void kasan_release_vmalloc(unsigned long start, unsigned long end,
+int __kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask);
+static inline int kasan_populate_vmalloc(unsigned long addr,
+					 unsigned long size, gfp_t gfp_mask)
+{
+	if (kasan_enabled())
+		return __kasan_populate_vmalloc(addr, size, gfp_mask);
+	return 0;
+}
+void __kasan_release_vmalloc(unsigned long start, unsigned long end,
 			   unsigned long free_region_start,
 			   unsigned long free_region_end,
 			   unsigned long flags);
+static inline void kasan_release_vmalloc(unsigned long start, unsigned long end,
+			   unsigned long free_region_start,
+			   unsigned long free_region_end,
+			   unsigned long flags)
+{
+	if (kasan_enabled())
+		return __kasan_release_vmalloc(start, end, free_region_start,
+					 free_region_end, flags);
+}
 
 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
 
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index d4c14359fea..22e5d67ff06 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -305,9 +305,6 @@ bool __kasan_slab_free(struct kmem_cache *cache, void *object, bool init,
 
 static inline bool check_page_allocation(void *ptr, unsigned long ip)
 {
-	if (!kasan_enabled())
-		return false;
-
 	if (ptr != page_address(virt_to_head_page(ptr))) {
 		kasan_report_invalid_free(ptr, ip, KASAN_REPORT_INVALID_FREE);
 		return true;
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index 516b49accc4..2b8e73f5f6a 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -506,9 +506,6 @@ static void release_alloc_meta(struct kasan_alloc_meta *meta)
 
 static void release_free_meta(const void *object, struct kasan_free_meta *meta)
 {
-	if (!kasan_enabled())
-		return;
-
 	/* Check if free meta is valid. */
 	if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_SLAB_FREE_META)
 		return;
diff --git a/mm/kasan/shadow.c b/mm/kasan/shadow.c
index 5d2a876035d..cf842b620a2 100644
--- a/mm/kasan/shadow.c
+++ b/mm/kasan/shadow.c
@@ -354,7 +354,7 @@ static int ___alloc_pages_bulk(struct page **pages, int nr_pages, gfp_t gfp_mask
 	return 0;
 }
 
-static int __kasan_populate_vmalloc(unsigned long start, unsigned long end, gfp_t gfp_mask)
+static int __kasan_populate_vmalloc_do(unsigned long start, unsigned long end, gfp_t gfp_mask)
 {
 	unsigned long nr_pages, nr_total = PFN_UP(end - start);
 	struct vmalloc_populate_data data;
@@ -403,14 +403,11 @@ static int __kasan_populate_vmalloc(unsigned long start, unsigned long end, gfp_
 	return ret;
 }
 
-int kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask)
+int __kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask)
 {
 	unsigned long shadow_start, shadow_end;
 	int ret;
 
-	if (!kasan_enabled())
-		return 0;
-
 	if (!is_vmalloc_or_module_addr((void *)addr))
 		return 0;
 
@@ -432,7 +429,7 @@ int kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mas
 	shadow_start = PAGE_ALIGN_DOWN(shadow_start);
 	shadow_end = PAGE_ALIGN(shadow_end);
 
-	ret = __kasan_populate_vmalloc(shadow_start, shadow_end, gfp_mask);
+	ret = __kasan_populate_vmalloc_do(shadow_start, shadow_end, gfp_mask);
 	if (ret)
 		return ret;
 
@@ -574,7 +571,7 @@ static int kasan_depopulate_vmalloc_pte(pte_t *ptep, unsigned long addr,
  * pages entirely covered by the free region, we will not run in to any
  * trouble - any simultaneous allocations will be for disjoint regions.
  */
-void kasan_release_vmalloc(unsigned long start, unsigned long end,
+void __kasan_release_vmalloc(unsigned long start, unsigned long end,
 			   unsigned long free_region_start,
 			   unsigned long free_region_end,
 			   unsigned long flags)
@@ -583,9 +580,6 @@ void kasan_release_vmalloc(unsigned long start, unsigned long end,
 	unsigned long region_start, region_end;
 	unsigned long size;
 
-	if (!kasan_enabled())
-		return;
-
 	region_start = ALIGN(start, KASAN_MEMORY_PER_SHADOW_PAGE);
 	region_end = ALIGN_DOWN(end, KASAN_MEMORY_PER_SHADOW_PAGE);
 
@@ -634,9 +628,6 @@ void *__kasan_unpoison_vmalloc(const void *start, unsigned long size,
 	 * with setting memory tags, so the KASAN_VMALLOC_INIT flag is ignored.
 	 */
 
-	if (!kasan_enabled())
-		return (void *)start;
-
 	if (!is_vmalloc_or_module_addr(start))
 		return (void *)start;
 
@@ -659,9 +650,6 @@ void *__kasan_unpoison_vmalloc(const void *start, unsigned long size,
  */
 void __kasan_poison_vmalloc(const void *start, unsigned long size)
 {
-	if (!kasan_enabled())
-		return;
-
 	if (!is_vmalloc_or_module_addr(start))
 		return;
 
-- 
2.34.1

Re: [PATCH 1/2] kasan: remove __kasan_save_free_info wrapper

[Andrey Konovalov]

On Thu, Oct 9, 2025 at 5:54 PM Sabyrzhan Tasbolatov <snovitoll@gmail.com> wrote:
>
> We don't need a kasan_enabled() check in
> kasan_save_free_info() at all. Both the higher level paths
> (kasan_slab_free and kasan_mempool_poison_object) already contain this
> check. Therefore, remove the __wrapper.
>
> Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
> Fixes: 1e338f4d99e6 ("kasan: introduce ARCH_DEFER_KASAN and unify static key across modes")
> ---
>  mm/kasan/generic.c | 2 +-
>  mm/kasan/kasan.h   | 7 +------
>  mm/kasan/tags.c    | 2 +-
>  3 files changed, 3 insertions(+), 8 deletions(-)
>
> diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
> index b413c46b3e0..516b49accc4 100644
> --- a/mm/kasan/generic.c
> +++ b/mm/kasan/generic.c
> @@ -573,7 +573,7 @@ void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags)
>         kasan_save_track(&alloc_meta->alloc_track, flags);
>  }
>
> -void __kasan_save_free_info(struct kmem_cache *cache, void *object)
> +void kasan_save_free_info(struct kmem_cache *cache, void *object)
>  {
>         struct kasan_free_meta *free_meta;
>
> diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
> index 07fa7375a84..fc9169a5476 100644
> --- a/mm/kasan/kasan.h
> +++ b/mm/kasan/kasan.h
> @@ -399,12 +399,7 @@ void kasan_set_track(struct kasan_track *track, depot_stack_handle_t stack);
>  void kasan_save_track(struct kasan_track *track, gfp_t flags);
>  void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags);
>
> -void __kasan_save_free_info(struct kmem_cache *cache, void *object);
> -static inline void kasan_save_free_info(struct kmem_cache *cache, void *object)
> -{
> -       if (kasan_enabled())
> -               __kasan_save_free_info(cache, object);
> -}
> +void kasan_save_free_info(struct kmem_cache *cache, void *object);
>
>  #ifdef CONFIG_KASAN_GENERIC
>  bool kasan_quarantine_put(struct kmem_cache *cache, void *object);
> diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c
> index b9f31293622..d65d48b85f9 100644
> --- a/mm/kasan/tags.c
> +++ b/mm/kasan/tags.c
> @@ -142,7 +142,7 @@ void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags)
>         save_stack_info(cache, object, flags, false);
>  }
>
> -void __kasan_save_free_info(struct kmem_cache *cache, void *object)
> +void kasan_save_free_info(struct kmem_cache *cache, void *object)
>  {
>         save_stack_info(cache, object, 0, true);
>  }
> --
> 2.34.1
>

Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>

Re: [PATCH 2/2] kasan: cleanup of kasan_enabled() checks

[Andrey Konovalov]

On Thu, Oct 9, 2025 at 5:54 PM Sabyrzhan Tasbolatov <snovitoll@gmail.com> wrote:
>
> Deduplication of kasan_enabled() checks which are already used by callers.
>
> * Altered functions:
>
> check_page_allocation
>         Delete the check because callers have it already in __wrappers in
>         include/linux/kasan.h:
>                 __kasan_kfree_large
>                 __kasan_mempool_poison_pages
>                 __kasan_mempool_poison_object
>
> kasan_populate_vmalloc, kasan_release_vmalloc
>         Add __wrappers in include/linux/kasan.h.
>         They are called externally in mm/vmalloc.c.
>
> __kasan_unpoison_vmalloc, __kasan_poison_vmalloc
>         Delete checks because there're already kasan_enabled() checks
>         in respective __wrappers in include/linux/kasan.h.
>
> release_free_meta -- Delete the check because the higher caller path
>         has it already. See the stack trace:
>
>         __kasan_slab_free -- has the check already
>         __kasan_mempool_poison_object -- has the check already
>                 poison_slab_object
>                         kasan_save_free_info
>                                 release_free_meta
>                                         kasan_enabled() -- Delete here
>
> Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
> ---
>  include/linux/kasan.h | 20 ++++++++++++++++++--
>  mm/kasan/common.c     |  3 ---
>  mm/kasan/generic.c    |  3 ---
>  mm/kasan/shadow.c     | 20 ++++----------------
>  4 files changed, 22 insertions(+), 24 deletions(-)
>
> diff --git a/include/linux/kasan.h b/include/linux/kasan.h
> index d12e1a5f5a9..f335c1d7b61 100644
> --- a/include/linux/kasan.h
> +++ b/include/linux/kasan.h
> @@ -571,11 +571,27 @@ static inline void kasan_init_hw_tags(void) { }
>  #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
>
>  void kasan_populate_early_vm_area_shadow(void *start, unsigned long size);
> -int kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask);
> -void kasan_release_vmalloc(unsigned long start, unsigned long end,
> +int __kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask);
> +static inline int kasan_populate_vmalloc(unsigned long addr,
> +                                        unsigned long size, gfp_t gfp_mask)
> +{
> +       if (kasan_enabled())
> +               return __kasan_populate_vmalloc(addr, size, gfp_mask);
> +       return 0;
> +}
> +void __kasan_release_vmalloc(unsigned long start, unsigned long end,
>                            unsigned long free_region_start,
>                            unsigned long free_region_end,
>                            unsigned long flags);
> +static inline void kasan_release_vmalloc(unsigned long start, unsigned long end,
> +                          unsigned long free_region_start,
> +                          unsigned long free_region_end,
> +                          unsigned long flags)
> +{
> +       if (kasan_enabled())
> +               return __kasan_release_vmalloc(start, end, free_region_start,
> +                                        free_region_end, flags);
> +}
>
>  #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
>
> diff --git a/mm/kasan/common.c b/mm/kasan/common.c
> index d4c14359fea..22e5d67ff06 100644
> --- a/mm/kasan/common.c
> +++ b/mm/kasan/common.c
> @@ -305,9 +305,6 @@ bool __kasan_slab_free(struct kmem_cache *cache, void *object, bool init,
>
>  static inline bool check_page_allocation(void *ptr, unsigned long ip)
>  {
> -       if (!kasan_enabled())
> -               return false;
> -
>         if (ptr != page_address(virt_to_head_page(ptr))) {
>                 kasan_report_invalid_free(ptr, ip, KASAN_REPORT_INVALID_FREE);
>                 return true;
> diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
> index 516b49accc4..2b8e73f5f6a 100644
> --- a/mm/kasan/generic.c
> +++ b/mm/kasan/generic.c
> @@ -506,9 +506,6 @@ static void release_alloc_meta(struct kasan_alloc_meta *meta)
>
>  static void release_free_meta(const void *object, struct kasan_free_meta *meta)
>  {
> -       if (!kasan_enabled())
> -               return;
> -
>         /* Check if free meta is valid. */
>         if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_SLAB_FREE_META)
>                 return;
> diff --git a/mm/kasan/shadow.c b/mm/kasan/shadow.c
> index 5d2a876035d..cf842b620a2 100644
> --- a/mm/kasan/shadow.c
> +++ b/mm/kasan/shadow.c
> @@ -354,7 +354,7 @@ static int ___alloc_pages_bulk(struct page **pages, int nr_pages, gfp_t gfp_mask
>         return 0;
>  }
>
> -static int __kasan_populate_vmalloc(unsigned long start, unsigned long end, gfp_t gfp_mask)
> +static int __kasan_populate_vmalloc_do(unsigned long start, unsigned long end, gfp_t gfp_mask)
>  {
>         unsigned long nr_pages, nr_total = PFN_UP(end - start);
>         struct vmalloc_populate_data data;
> @@ -403,14 +403,11 @@ static int __kasan_populate_vmalloc(unsigned long start, unsigned long end, gfp_
>         return ret;
>  }
>
> -int kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask)
> +int __kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask)
>  {
>         unsigned long shadow_start, shadow_end;
>         int ret;
>
> -       if (!kasan_enabled())
> -               return 0;
> -
>         if (!is_vmalloc_or_module_addr((void *)addr))
>                 return 0;
>
> @@ -432,7 +429,7 @@ int kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mas
>         shadow_start = PAGE_ALIGN_DOWN(shadow_start);
>         shadow_end = PAGE_ALIGN(shadow_end);
>
> -       ret = __kasan_populate_vmalloc(shadow_start, shadow_end, gfp_mask);
> +       ret = __kasan_populate_vmalloc_do(shadow_start, shadow_end, gfp_mask);
>         if (ret)
>                 return ret;
>
> @@ -574,7 +571,7 @@ static int kasan_depopulate_vmalloc_pte(pte_t *ptep, unsigned long addr,
>   * pages entirely covered by the free region, we will not run in to any
>   * trouble - any simultaneous allocations will be for disjoint regions.
>   */
> -void kasan_release_vmalloc(unsigned long start, unsigned long end,
> +void __kasan_release_vmalloc(unsigned long start, unsigned long end,
>                            unsigned long free_region_start,
>                            unsigned long free_region_end,
>                            unsigned long flags)
> @@ -583,9 +580,6 @@ void kasan_release_vmalloc(unsigned long start, unsigned long end,
>         unsigned long region_start, region_end;
>         unsigned long size;
>
> -       if (!kasan_enabled())
> -               return;
> -
>         region_start = ALIGN(start, KASAN_MEMORY_PER_SHADOW_PAGE);
>         region_end = ALIGN_DOWN(end, KASAN_MEMORY_PER_SHADOW_PAGE);
>
> @@ -634,9 +628,6 @@ void *__kasan_unpoison_vmalloc(const void *start, unsigned long size,
>          * with setting memory tags, so the KASAN_VMALLOC_INIT flag is ignored.
>          */
>
> -       if (!kasan_enabled())
> -               return (void *)start;
> -
>         if (!is_vmalloc_or_module_addr(start))
>                 return (void *)start;
>
> @@ -659,9 +650,6 @@ void *__kasan_unpoison_vmalloc(const void *start, unsigned long size,
>   */
>  void __kasan_poison_vmalloc(const void *start, unsigned long size)
>  {
> -       if (!kasan_enabled())
> -               return;
> -
>         if (!is_vmalloc_or_module_addr(start))
>                 return;
>
> --
> 2.34.1
>

Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>

Awesome, thank you!

I believe the check in kasan_byte_accessible() can be just removed as
well? If you do, please run the tests to be sure.

As for the other three (check_inline_region(), kasan_poison(), and
kasan_poison_last_granule()) - perhaps, we can leave them be.
Otherwise, we would need to duplicate the kasan_enabled() checks in a
lot of compiler-inserted functions.