From: Catalin Marinas catalin.marinas@arm.com
[ Upstream commit 6d05141a393071e104bf5be5ad4d0c79c6dff343 ]
Currently post_alloc_hook() skips the kasan unpoisoning if the tags will be zeroed (__GFP_ZEROTAGS) or __GFP_SKIP_KASAN_UNPOISON is passed. Since __GFP_ZEROTAGS is now accompanied by __GFP_SKIP_KASAN_UNPOISON, remove the extra check.
Signed-off-by: Catalin Marinas catalin.marinas@arm.com Cc: Andrey Ryabinin ryabinin.a.a@gmail.com Cc: Andrey Konovalov andreyknvl@gmail.com Cc: Peter Collingbourne pcc@google.com Cc: Vincenzo Frascino vincenzo.frascino@arm.com Reviewed-by: Vincenzo Frascino vincenzo.frascino@arm.com Reviewed-by: Andrey Konovalov andreyknvl@gmail.com Link: https://lore.kernel.org/r/20220610152141.2148929-4-catalin.marinas@arm.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- mm/page_alloc.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 4d5c30dc757f..b0bcab50f0a3 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2361,7 +2361,7 @@ static inline bool check_new_pcp(struct page *page, unsigned int order) } #endif /* CONFIG_DEBUG_VM */
-static inline bool should_skip_kasan_unpoison(gfp_t flags, bool init_tags) +static inline bool should_skip_kasan_unpoison(gfp_t flags) { /* Don't skip if a software KASAN mode is enabled. */ if (IS_ENABLED(CONFIG_KASAN_GENERIC) || @@ -2373,12 +2373,10 @@ static inline bool should_skip_kasan_unpoison(gfp_t flags, bool init_tags) return true;
/* - * With hardware tag-based KASAN enabled, skip if either: - * - * 1. Memory tags have already been cleared via tag_clear_highpage(). - * 2. Skipping has been requested via __GFP_SKIP_KASAN_UNPOISON. + * With hardware tag-based KASAN enabled, skip if this has been + * requested via __GFP_SKIP_KASAN_UNPOISON. */ - return init_tags || (flags & __GFP_SKIP_KASAN_UNPOISON); + return flags & __GFP_SKIP_KASAN_UNPOISON; }
static inline bool should_skip_init(gfp_t flags) @@ -2430,7 +2428,7 @@ inline void post_alloc_hook(struct page *page, unsigned int order, /* Note that memory is already initialized by the loop above. */ init = false; } - if (!should_skip_kasan_unpoison(gfp_flags, init_tags)) { + if (!should_skip_kasan_unpoison(gfp_flags)) { /* Unpoison shadow memory or set memory tags. */ kasan_unpoison_pages(page, order, init);