[PATCH v3 31/39] arm64: kasan: Align allocations for HW_TAGS

Andrey Konovalov
2020-09-24T22:52:23Z

Hardware tag-based KASAN uses the memory tagging approach, which requires
all allocations to be aligned to the memory granule size. Align the
allocations to MTE_GRANULE_SIZE via ARCH_SLAB_MINALIGN when
CONFIG_KASAN_HW_TAGS is enabled.

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>
---
Change-Id: I51ebd3f9645e6330e5a92973bf7c86b62d632c2b
---
arch/arm64/include/asm/cache.h | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/arm64/include/asm/cache.h b/arch/arm64/include/asm/cache.h
index a4d1b5f771f6..151808f1f443 100644
--- a/arch/arm64/include/asm/cache.h
+++ b/arch/arm64/include/asm/cache.h
@@ -6,6 +6,7 @@
#define __ASM_CACHE_H

#include <asm/cputype.h>
+#include <asm/mte-kasan.h>

#define CTR_L1IP_SHIFT 14
#define CTR_L1IP_MASK 3
@@ -50,6 +51,8 @@

#ifdef CONFIG_KASAN_SW_TAGS
#define ARCH_SLAB_MINALIGN (1ULL << KASAN_SHADOW_SCALE_SHIFT)
+#elif defined(CONFIG_KASAN_HW_TAGS)
+#define ARCH_SLAB_MINALIGN MTE_GRANULE_SIZE
#endif

#ifndef __ASSEMBLY__
--
2.28.0.681.g6f77f65b4e-goog