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-rw-r--r--arch/riscv/include/asm/kasan.h32
1 files changed, 26 insertions, 6 deletions
diff --git a/arch/riscv/include/asm/kasan.h b/arch/riscv/include/asm/kasan.h
index b04028c6218c..0b85e363e778 100644
--- a/arch/riscv/include/asm/kasan.h
+++ b/arch/riscv/include/asm/kasan.h
@@ -8,17 +8,37 @@
#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_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE)
-
-#define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << \
- (64 - KASAN_SHADOW_SCALE_SHIFT)))
+#define KASAN_SHADOW_SIZE (UL(1) << ((VA_BITS - 1) - KASAN_SHADOW_SCALE_SHIFT))
+/*
+ * Depending on the size of the virtual address space, the region may not be
+ * aligned on PGDIR_SIZE, so force its alignment to ease its population.
+ */
+#define KASAN_SHADOW_START ((KASAN_SHADOW_END - KASAN_SHADOW_SIZE) & PGDIR_MASK)
+#define KASAN_SHADOW_END MODULES_LOWEST_VADDR
+#define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
void kasan_init(void);
asmlinkage void kasan_early_init(void);
+void kasan_swapper_init(void);
#endif
#endif