| Message ID | 64f8b74a4766f886a6df77438e7e098205fd0863.1638308023.git.andreyknvl@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | kasan, vmalloc, arm64: add vmalloc tagging support for SW/HW_TAGS | expand |
On Tue, Nov 30, 2021 at 10:40 PM <andrey.konovalov@linux.dev> wrote: > > From: Andrey Konovalov <andreyknvl@google.com> > > Currently, the code responsible for initializing and poisoning memory > in free_pages_prepare() is scattered across two locations: > kasan_free_pages() for HW_TAGS KASAN and free_pages_prepare() itself. > This is confusing. > > This and a few following patches combine the code from these two > locations. Along the way, these patches also simplify the performed > checks to make them easier to follow. > > This patch replaces the only caller of kasan_free_pages() with its > implementation. > > As kasan_has_integrated_init() is only true when CONFIG_KASAN_HW_TAGS > is enabled, moving the code does no functional changes. > > This patch is not useful by itself but makes the simplifications in > the following patches easier to follow. > > Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Alexander Potapenko <glider@google.com> > --- > include/linux/kasan.h | 8 -------- > mm/kasan/common.c | 2 +- > mm/kasan/hw_tags.c | 11 ----------- > mm/page_alloc.c | 6 ++++-- > 4 files changed, 5 insertions(+), 22 deletions(-) > > diff --git a/include/linux/kasan.h b/include/linux/kasan.h > index d8783b682669..89a43d8ae4fe 100644 > --- a/include/linux/kasan.h > +++ b/include/linux/kasan.h > @@ -95,7 +95,6 @@ static inline bool kasan_hw_tags_enabled(void) > } > > void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags); > -void kasan_free_pages(struct page *page, unsigned int order); > > #else /* CONFIG_KASAN_HW_TAGS */ > > @@ -116,13 +115,6 @@ static __always_inline void kasan_alloc_pages(struct page *page, > BUILD_BUG(); > } > > -static __always_inline void kasan_free_pages(struct page *page, > - unsigned int order) > -{ > - /* Only available for integrated init. */ > - BUILD_BUG(); > -} > - > #endif /* CONFIG_KASAN_HW_TAGS */ > > static inline bool kasan_has_integrated_init(void) > diff --git a/mm/kasan/common.c b/mm/kasan/common.c > index 8428da2aaf17..66078cc1b4f0 100644 > --- a/mm/kasan/common.c > +++ b/mm/kasan/common.c > @@ -387,7 +387,7 @@ static inline bool ____kasan_kfree_large(void *ptr, unsigned long ip) > } > > /* > - * The object will be poisoned by kasan_free_pages() or > + * The object will be poisoned by kasan_poison_pages() or > * kasan_slab_free_mempool(). > */ > > diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c > index 7355cb534e4f..0b8225add2e4 100644 > --- a/mm/kasan/hw_tags.c > +++ b/mm/kasan/hw_tags.c > @@ -213,17 +213,6 @@ void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags) > } > } > > -void kasan_free_pages(struct page *page, unsigned int order) > -{ > - /* > - * This condition should match the one in free_pages_prepare() in > - * page_alloc.c. > - */ > - bool init = want_init_on_free(); > - > - kasan_poison_pages(page, order, init); > -} > - > #if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) > > void kasan_enable_tagging_sync(void) > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 3589333b5b77..3f3ea41f8c64 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1353,15 +1353,17 @@ static __always_inline bool free_pages_prepare(struct page *page, > > /* > * As memory initialization might be integrated into KASAN, > - * kasan_free_pages and kernel_init_free_pages must be > + * KASAN poisoning and memory initialization code must be > * kept together to avoid discrepancies in behavior. > * > * With hardware tag-based KASAN, memory tags must be set before the > * page becomes unavailable via debug_pagealloc or arch_free_page. > */ > if (kasan_has_integrated_init()) { > + bool init = want_init_on_free(); > + > if (!skip_kasan_poison) > - kasan_free_pages(page, order); > + kasan_poison_pages(page, order, init); > } else { > bool init = want_init_on_free(); > > -- > 2.25.1 > > -- > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@googlegroups.com. > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/64f8b74a4766f886a6df77438e7e098205fd0863.1638308023.git.andreyknvl%40google.com.
diff --git a/include/linux/kasan.h b/include/linux/kasan.h index d8783b682669..89a43d8ae4fe 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -95,7 +95,6 @@ static inline bool kasan_hw_tags_enabled(void) } void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags); -void kasan_free_pages(struct page *page, unsigned int order); #else /* CONFIG_KASAN_HW_TAGS */ @@ -116,13 +115,6 @@ static __always_inline void kasan_alloc_pages(struct page *page, BUILD_BUG(); } -static __always_inline void kasan_free_pages(struct page *page, - unsigned int order) -{ - /* Only available for integrated init. */ - BUILD_BUG(); -} - #endif /* CONFIG_KASAN_HW_TAGS */ static inline bool kasan_has_integrated_init(void) diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 8428da2aaf17..66078cc1b4f0 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -387,7 +387,7 @@ static inline bool ____kasan_kfree_large(void *ptr, unsigned long ip) } /* - * The object will be poisoned by kasan_free_pages() or + * The object will be poisoned by kasan_poison_pages() or * kasan_slab_free_mempool(). */ diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c index 7355cb534e4f..0b8225add2e4 100644 --- a/mm/kasan/hw_tags.c +++ b/mm/kasan/hw_tags.c @@ -213,17 +213,6 @@ void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags) } } -void kasan_free_pages(struct page *page, unsigned int order) -{ - /* - * This condition should match the one in free_pages_prepare() in - * page_alloc.c. - */ - bool init = want_init_on_free(); - - kasan_poison_pages(page, order, init); -} - #if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) void kasan_enable_tagging_sync(void) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 3589333b5b77..3f3ea41f8c64 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1353,15 +1353,17 @@ static __always_inline bool free_pages_prepare(struct page *page, /* * As memory initialization might be integrated into KASAN, - * kasan_free_pages and kernel_init_free_pages must be + * KASAN poisoning and memory initialization code must be * kept together to avoid discrepancies in behavior. * * With hardware tag-based KASAN, memory tags must be set before the * page becomes unavailable via debug_pagealloc or arch_free_page. */ if (kasan_has_integrated_init()) { + bool init = want_init_on_free(); + if (!skip_kasan_poison) - kasan_free_pages(page, order); + kasan_poison_pages(page, order, init); } else { bool init = want_init_on_free();