From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Use the KASAN_TAG_KERNEL marco instead of open-coding 0xff in the mm
code. This macro is provided by include/linux/kasan-tags.h, which does
not include any other headers, so it's safe to include it into mm.h
without causing circular include dependencies.
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
---
include/linux/kasan.h | 1 +
include/linux/mm.h | 4 ++--
mm/page_alloc.c | 2 +-
3 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index d49e3d4c099e..dbb06d789e74 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -4,6 +4,7 @@
#include <linux/bug.h>
#include <linux/kasan-enabled.h>
+#include <linux/kasan-tags.h>
#include <linux/kernel.h>
#include <linux/static_key.h>
#include <linux/types.h>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index a422cc123a2d..8b2e4841e817 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1815,7 +1815,7 @@ static inline void vma_set_access_pid_bit(struct vm_area_struct *vma)
static inline u8 page_kasan_tag(const struct page *page)
{
- u8 tag = 0xff;
+ u8 tag = KASAN_TAG_KERNEL;
if (kasan_enabled()) {
tag = (page->flags >> KASAN_TAG_PGSHIFT) & KASAN_TAG_MASK;
@@ -1844,7 +1844,7 @@ static inline void page_kasan_tag_set(struct page *page, u8 tag)
static inline void page_kasan_tag_reset(struct page *page)
{
if (kasan_enabled())
- page_kasan_tag_set(page, 0xff);
+ page_kasan_tag_set(page, KASAN_TAG_KERNEL);
}
#else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 7ea9c33320bf..51e85760877a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1059,7 +1059,7 @@ static inline bool should_skip_kasan_poison(struct page *page, fpi_t fpi_flags)
if (IS_ENABLED(CONFIG_KASAN_GENERIC))
return deferred_pages_enabled();
- return page_kasan_tag(page) == 0xff;
+ return page_kasan_tag(page) == KASAN_TAG_KERNEL;
}
static void kernel_init_pages(struct page *page, int numpages)
--
2.25.1
