diff options
| -rw-r--r-- | arch/riscv/include/asm/kasan.h | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/arch/riscv/include/asm/kasan.h b/arch/riscv/include/asm/kasan.h index b04028c6218c..a2b3d9cdbc86 100644 --- a/arch/riscv/include/asm/kasan.h +++ b/arch/riscv/include/asm/kasan.h @@ -8,12 +8,28 @@ #ifdef CONFIG_KASAN +/* + * The following comment was copied from arm64: + * KASAN_SHADOW_START: beginning of the kernel virtual addresses. + * KASAN_SHADOW_END: KASAN_SHADOW_START + 1/N of kernel virtual addresses, + * where N = (1 << KASAN_SHADOW_SCALE_SHIFT). + * + * KASAN_SHADOW_OFFSET: + * This value is used to map an address to the corresponding shadow + * address by the following formula: + * shadow_addr = (address >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET + * + * (1 << (64 - KASAN_SHADOW_SCALE_SHIFT)) shadow addresses that lie in range + * [KASAN_SHADOW_OFFSET, KASAN_SHADOW_END) cover all 64-bits of virtual + * addresses. So KASAN_SHADOW_OFFSET should satisfy the following equation: + * KASAN_SHADOW_OFFSET = KASAN_SHADOW_END - + * (1ULL << (64 - KASAN_SHADOW_SCALE_SHIFT)) + */ #define KASAN_SHADOW_SCALE_SHIFT 3 -#define KASAN_SHADOW_SIZE (UL(1) << (38 - KASAN_SHADOW_SCALE_SHIFT)) -#define KASAN_SHADOW_START KERN_VIRT_START /* 2^64 - 2^38 */ +#define KASAN_SHADOW_SIZE (UL(1) << ((CONFIG_VA_BITS - 1) - KASAN_SHADOW_SCALE_SHIFT)) +#define KASAN_SHADOW_START KERN_VIRT_START #define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE) - #define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << \ (64 - KASAN_SHADOW_SCALE_SHIFT))) |