diff options
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 31 |
1 files changed, 22 insertions, 9 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 350bb27dc4bb..59a9408e1e7d 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2343,6 +2343,26 @@ 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) +{ + /* Don't skip if a software KASAN mode is enabled. */ + if (IS_ENABLED(CONFIG_KASAN_GENERIC) || + IS_ENABLED(CONFIG_KASAN_SW_TAGS)) + return false; + + /* Skip, if hardware tag-based KASAN is not enabled. */ + if (!kasan_hw_tags_enabled()) + 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. + */ + return init_tags || (flags & __GFP_SKIP_KASAN_UNPOISON); +} + inline void post_alloc_hook(struct page *page, unsigned int order, gfp_t gfp_flags) { @@ -2382,15 +2402,8 @@ inline void post_alloc_hook(struct page *page, unsigned int order, /* Note that memory is already initialized by the loop above. */ init = false; } - /* - * If either a software KASAN mode is enabled, or, - * in the case of hardware tag-based KASAN, - * if memory tags have not been cleared via tag_clear_highpage(). - */ - if (IS_ENABLED(CONFIG_KASAN_GENERIC) || - IS_ENABLED(CONFIG_KASAN_SW_TAGS) || - kasan_hw_tags_enabled() && !init_tags) { - /* Mark shadow memory or set memory tags. */ + if (!should_skip_kasan_unpoison(gfp_flags, init_tags)) { + /* Unpoison shadow memory or set memory tags. */ kasan_unpoison_pages(page, order, init); /* Note that memory is already initialized by KASAN. */ |