diff options
| author | Andrey Konovalov <andreyknvl@google.com> | 2022-03-24 18:11:26 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-24 19:06:47 -0700 |
| commit | 53ae233c30a623ff44ff2f83854e92530c5d9fc2 (patch) | |
| tree | a6fb500753f2d2a89a70c842ac91831582e75c0b /include/linux/gfp.h | |
| parent | f49d9c5bb15cc5c470097078ec1f26ff605ae1a2 (diff) | |
kasan, page_alloc: allow skipping unpoisoning for HW_TAGS
Add a new GFP flag __GFP_SKIP_KASAN_UNPOISON that allows skipping KASAN
poisoning for page_alloc allocations. The flag is only effective with
HW_TAGS KASAN.
This flag will be used by vmalloc code for page_alloc allocations backing
vmalloc() mappings in a following patch. The reason to skip KASAN
poisoning for these pages in page_alloc is because vmalloc code will be
poisoning them instead.
Also reword the comment for __GFP_SKIP_KASAN_POISON.
Link: https://lkml.kernel.org/r/35c97d77a704f6ff971dd3bfe4be95855744108e.1643047180.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/gfp.h')
| -rw-r--r-- | include/linux/gfp.h | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 75abf8d5bc9b..688a39fde43e 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -55,12 +55,14 @@ struct vm_area_struct; #define ___GFP_ACCOUNT 0x400000u #define ___GFP_ZEROTAGS 0x800000u #ifdef CONFIG_KASAN_HW_TAGS -#define ___GFP_SKIP_KASAN_POISON 0x1000000u +#define ___GFP_SKIP_KASAN_UNPOISON 0x1000000u +#define ___GFP_SKIP_KASAN_POISON 0x2000000u #else +#define ___GFP_SKIP_KASAN_UNPOISON 0 #define ___GFP_SKIP_KASAN_POISON 0 #endif #ifdef CONFIG_LOCKDEP -#define ___GFP_NOLOCKDEP 0x2000000u +#define ___GFP_NOLOCKDEP 0x4000000u #else #define ___GFP_NOLOCKDEP 0 #endif @@ -241,22 +243,25 @@ struct vm_area_struct; * intended for optimization: setting memory tags at the same time as zeroing * memory has minimal additional performace impact. * - * %__GFP_SKIP_KASAN_POISON returns a page which does not need to be poisoned - * on deallocation. Typically used for userspace pages. Currently only has an - * effect in HW tags mode. + * %__GFP_SKIP_KASAN_UNPOISON makes KASAN skip unpoisoning on page allocation. + * Only effective in HW_TAGS mode. + * + * %__GFP_SKIP_KASAN_POISON makes KASAN skip poisoning on page deallocation. + * Typically, used for userspace pages. Only effective in HW_TAGS mode. */ #define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN) #define __GFP_COMP ((__force gfp_t)___GFP_COMP) #define __GFP_ZERO ((__force gfp_t)___GFP_ZERO) #define __GFP_ZEROTAGS ((__force gfp_t)___GFP_ZEROTAGS) -#define __GFP_SKIP_KASAN_POISON ((__force gfp_t)___GFP_SKIP_KASAN_POISON) +#define __GFP_SKIP_KASAN_UNPOISON ((__force gfp_t)___GFP_SKIP_KASAN_UNPOISON) +#define __GFP_SKIP_KASAN_POISON ((__force gfp_t)___GFP_SKIP_KASAN_POISON) /* Disable lockdep for GFP context tracking */ #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP) /* Room for N __GFP_FOO bits */ -#define __GFP_BITS_SHIFT (24 + \ - IS_ENABLED(CONFIG_KASAN_HW_TAGS) + \ +#define __GFP_BITS_SHIFT (24 + \ + 2 * IS_ENABLED(CONFIG_KASAN_HW_TAGS) + \ IS_ENABLED(CONFIG_LOCKDEP)) #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1)) |