diff options
| author | Andrey Konovalov <andreyknvl@google.com> | 2018-12-28 00:30:31 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-12-28 12:11:43 -0800 |
| commit | 21696c1613244f2ad4e9216c4f6e7804831a992c (patch) | |
| tree | e6c87ca92199cdff892ee99afe2a3c7f3d960380 /arch | |
| parent | 356607f21e603523d4b0a4f918722845214fc6a8 (diff) | |
kasan, arm64: enable top byte ignore for the kernel
Tag-based KASAN uses the Top Byte Ignore feature of arm64 CPUs to store a
pointer tag in the top byte of each pointer. This commit enables the
TCR_TBI1 bit, which enables Top Byte Ignore for the kernel, when tag-based
KASAN is used.
Link: http://lkml.kernel.org/r/f51eca084c8cdb2f3a55195fe342dc8953b7aead.1544099024.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Mark Rutland <mark.rutland@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/pgtable-hwdef.h | 1 | ||||
| -rw-r--r-- | arch/arm64/mm/proc.S | 8 |
2 files changed, 8 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index 22bb3ae514f5..e9b0a7d75184 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -299,6 +299,7 @@ #define TCR_A1 (UL(1) << 22) #define TCR_ASID16 (UL(1) << 36) #define TCR_TBI0 (UL(1) << 37) +#define TCR_TBI1 (UL(1) << 38) #define TCR_HA (UL(1) << 39) #define TCR_HD (UL(1) << 40) #define TCR_NFD1 (UL(1) << 54) diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index e05b3ce1db6b..73886a5f1f30 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -47,6 +47,12 @@ /* PTWs cacheable, inner/outer WBWA */ #define TCR_CACHE_FLAGS TCR_IRGN_WBWA | TCR_ORGN_WBWA +#ifdef CONFIG_KASAN_SW_TAGS +#define TCR_KASAN_FLAGS TCR_TBI1 +#else +#define TCR_KASAN_FLAGS 0 +#endif + #define MAIR(attr, mt) ((attr) << ((mt) * 8)) /* @@ -449,7 +455,7 @@ ENTRY(__cpu_setup) */ ldr x10, =TCR_TxSZ(VA_BITS) | TCR_CACHE_FLAGS | TCR_SMP_FLAGS | \ TCR_TG_FLAGS | TCR_KASLR_FLAGS | TCR_ASID16 | \ - TCR_TBI0 | TCR_A1 + TCR_TBI0 | TCR_A1 | TCR_KASAN_FLAGS #ifdef CONFIG_ARM64_USER_VA_BITS_52 ldr_l x9, vabits_user |