diff options
| author | Steve Capper <steve.capper@arm.com> | 2019-08-07 18:55:14 +0300 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2019-08-09 13:16:51 +0300 |
| commit | 14c127c957c1c6070647c171e72f06e0db275ebf (patch) | |
| tree | 6f5e57a4dd8c8cbe895b01513c2bd6a1cb3ddcff /arch/arm64/include/asm/memory.h | |
| parent | 9cb1c5ddd2c432834dd4f40c0170d6b639e8e5c3 (diff) | |
| download | linux-14c127c957c1c6070647c171e72f06e0db275ebf.tar.xz | |
arm64: mm: Flip kernel VA space
In order to allow for a KASAN shadow that changes size at boot time, one
must fix the KASAN_SHADOW_END for both 48 & 52-bit VAs and "grow" the
start address. Also, it is highly desirable to maintain the same
function addresses in the kernel .text between VA sizes. Both of these
requirements necessitate us to flip the kernel address space halves s.t.
the direct linear map occupies the lower addresses.
This patch puts the direct linear map in the lower addresses of the
kernel VA range and everything else in the higher ranges.
We need to adjust:
*) KASAN shadow region placement logic,
*) KASAN_SHADOW_OFFSET computation logic,
*) virt_to_phys, phys_to_virt checks,
*) page table dumper.
These are all small changes, that need to take place atomically, so they
are bundled into this commit.
As part of the re-arrangement, a guard region of 2MB (to preserve
alignment for fixed map) is added after the vmemmap. Otherwise the
vmemmap could intersect with IS_ERR pointers.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/include/asm/memory.h')
| -rw-r--r-- | arch/arm64/include/asm/memory.h | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 98fda92a2612..380594b1a0ba 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -38,9 +38,9 @@ */ #define VA_BITS (CONFIG_ARM64_VA_BITS) #define VA_START (UL(0xffffffffffffffff) - \ - (UL(1) << VA_BITS) + 1) -#define PAGE_OFFSET (UL(0xffffffffffffffff) - \ (UL(1) << (VA_BITS - 1)) + 1) +#define PAGE_OFFSET (UL(0xffffffffffffffff) - \ + (UL(1) << VA_BITS) + 1) #define KIMAGE_VADDR (MODULES_END) #define BPF_JIT_REGION_START (VA_START + KASAN_SHADOW_SIZE) #define BPF_JIT_REGION_SIZE (SZ_128M) @@ -48,7 +48,7 @@ #define MODULES_END (MODULES_VADDR + MODULES_VSIZE) #define MODULES_VADDR (BPF_JIT_REGION_END) #define MODULES_VSIZE (SZ_128M) -#define VMEMMAP_START (PAGE_OFFSET - VMEMMAP_SIZE) +#define VMEMMAP_START (-VMEMMAP_SIZE - SZ_2M) #define PCI_IO_END (VMEMMAP_START - SZ_2M) #define PCI_IO_START (PCI_IO_END - PCI_IO_SIZE) #define FIXADDR_TOP (PCI_IO_START - SZ_2M) @@ -231,7 +231,7 @@ static inline const void *__tag_set(const void *addr, u8 tag) * space. Testing the top bit for the start of the region is a * sufficient check. */ -#define __is_lm_address(addr) (!!((addr) & BIT(VA_BITS - 1))) +#define __is_lm_address(addr) (!((addr) & BIT(VA_BITS - 1))) #define __lm_to_phys(addr) (((addr) & ~PAGE_OFFSET) + PHYS_OFFSET) #define __kimg_to_phys(addr) ((addr) - kimage_voffset) |