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| author | Andrey Konovalov <andreyknvl@google.com> | 2020-12-22 12:00:53 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-12-22 12:55:07 -0800 |
| commit | afe6ef80dcecf2cf7ccab0d94257b985e4c47d80 (patch) | |
| tree | 65b72fca55595313a6f8aa7d30a637c44d4959df /arch | |
| parent | 97fc712232368ddeabd91cdabf40da9b2155c033 (diff) | |
| download | lwn-afe6ef80dcecf2cf7ccab0d94257b985e4c47d80.tar.gz lwn-afe6ef80dcecf2cf7ccab0d94257b985e4c47d80.zip | |
kasan, arm64: only init shadow for software modes
This is a preparatory commit for the upcoming addition of a new hardware
tag-based (MTE-based) KASAN mode.
Hardware tag-based KASAN won't be using shadow memory. Only initialize it
when one of the software KASAN modes are enabled.
No functional changes for software modes.
Link: https://lkml.kernel.org/r/d1742eea2cd728d150d49b144e49b6433405c7ba.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/include/asm/kasan.h | 8 | ||||
| -rw-r--r-- | arch/arm64/mm/kasan_init.c | 15 |
2 files changed, 20 insertions, 3 deletions
diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h index b0dc4abc3589..f7ea70d02cab 100644 --- a/arch/arm64/include/asm/kasan.h +++ b/arch/arm64/include/asm/kasan.h @@ -13,6 +13,12 @@ #define arch_kasan_get_tag(addr) __tag_get(addr) #ifdef CONFIG_KASAN +void kasan_init(void); +#else +static inline void kasan_init(void) { } +#endif + +#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) /* * KASAN_SHADOW_START: beginning of the kernel virtual addresses. @@ -33,12 +39,10 @@ #define _KASAN_SHADOW_START(va) (KASAN_SHADOW_END - (1UL << ((va) - KASAN_SHADOW_SCALE_SHIFT))) #define KASAN_SHADOW_START _KASAN_SHADOW_START(vabits_actual) -void kasan_init(void); void kasan_copy_shadow(pgd_t *pgdir); asmlinkage void kasan_early_init(void); #else -static inline void kasan_init(void) { } static inline void kasan_copy_shadow(pgd_t *pgdir) { } #endif diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c index b24e43d20667..ffeb80d5aa8d 100644 --- a/arch/arm64/mm/kasan_init.c +++ b/arch/arm64/mm/kasan_init.c @@ -21,6 +21,8 @@ #include <asm/sections.h> #include <asm/tlbflush.h> +#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) + static pgd_t tmp_pg_dir[PTRS_PER_PGD] __initdata __aligned(PGD_SIZE); /* @@ -208,7 +210,7 @@ static void __init clear_pgds(unsigned long start, set_pgd(pgd_offset_k(start), __pgd(0)); } -void __init kasan_init(void) +static void __init kasan_init_shadow(void) { u64 kimg_shadow_start, kimg_shadow_end; u64 mod_shadow_start, mod_shadow_end; @@ -269,6 +271,17 @@ void __init kasan_init(void) memset(kasan_early_shadow_page, KASAN_SHADOW_INIT, PAGE_SIZE); cpu_replace_ttbr1(lm_alias(swapper_pg_dir)); +} + +#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) */ + +static inline void __init kasan_init_shadow(void) { } + +#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ + +void __init kasan_init(void) +{ + kasan_init_shadow(); /* At this point kasan is fully initialized. Enable error messages */ init_task.kasan_depth = 0; |