diff options
Diffstat (limited to 'arch/arm64/include/asm/memory.h')
| -rw-r--r-- | arch/arm64/include/asm/memory.h | 66 |
1 files changed, 62 insertions, 4 deletions
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 32f82723338a..f7c4d2146aed 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -25,6 +25,7 @@ #include <linux/const.h> #include <linux/types.h> #include <asm/bug.h> +#include <asm/page-def.h> #include <asm/sizes.h> /* @@ -64,8 +65,10 @@ * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area. */ #define VA_BITS (CONFIG_ARM64_VA_BITS) -#define VA_START (UL(0xffffffffffffffff) << VA_BITS) -#define PAGE_OFFSET (UL(0xffffffffffffffff) << (VA_BITS - 1)) +#define VA_START (UL(0xffffffffffffffff) - \ + (UL(1) << VA_BITS) + 1) +#define PAGE_OFFSET (UL(0xffffffffffffffff) - \ + (UL(1) << (VA_BITS - 1)) + 1) #define KIMAGE_VADDR (MODULES_END) #define MODULES_END (MODULES_VADDR + MODULES_VSIZE) #define MODULES_VADDR (VA_START + KASAN_SHADOW_SIZE) @@ -92,13 +95,68 @@ #define KERNEL_END _end /* - * The size of the KASAN shadow region. This should be 1/8th of the - * size of the entire kernel virtual address space. + * KASAN requires 1/8th of the kernel virtual address space for the shadow + * region. KASAN can bloat the stack significantly, so double the (minimum) + * stack size when KASAN is in use. */ #ifdef CONFIG_KASAN #define KASAN_SHADOW_SIZE (UL(1) << (VA_BITS - 3)) +#define KASAN_THREAD_SHIFT 1 #else #define KASAN_SHADOW_SIZE (0) +#define KASAN_THREAD_SHIFT 0 +#endif + +#define MIN_THREAD_SHIFT (14 + KASAN_THREAD_SHIFT) + +/* + * VMAP'd stacks are allocated at page granularity, so we must ensure that such + * stacks are a multiple of page size. + */ +#if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT) +#define THREAD_SHIFT PAGE_SHIFT +#else +#define THREAD_SHIFT MIN_THREAD_SHIFT +#endif + +#if THREAD_SHIFT >= PAGE_SHIFT +#define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT) +#endif + +#define THREAD_SIZE (UL(1) << THREAD_SHIFT) + +/* + * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by + * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry + * assembly. + */ +#ifdef CONFIG_VMAP_STACK +#define THREAD_ALIGN (2 * THREAD_SIZE) +#else +#define THREAD_ALIGN THREAD_SIZE +#endif + +#define IRQ_STACK_SIZE THREAD_SIZE + +#define OVERFLOW_STACK_SIZE SZ_4K + +/* + * Alignment of kernel segments (e.g. .text, .data). + */ +#if defined(CONFIG_DEBUG_ALIGN_RODATA) +/* + * 4 KB granule: 1 level 2 entry + * 16 KB granule: 128 level 3 entries, with contiguous bit + * 64 KB granule: 32 level 3 entries, with contiguous bit + */ +#define SEGMENT_ALIGN SZ_2M +#else +/* + * 4 KB granule: 16 level 3 entries, with contiguous bit + * 16 KB granule: 4 level 3 entries, without contiguous bit + * 64 KB granule: 1 level 3 entry + */ +#define SEGMENT_ALIGN SZ_64K #endif /* |