diff options
| author | Steve Capper <steve.capper@arm.com> | 2019-08-07 18:55:17 +0300 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2019-08-09 13:17:16 +0300 |
| commit | 90ec95cda91a021d82351c976896a63aa364ebf1 (patch) | |
| tree | 6f5295463a65f0cda5e79bd47998ab10df11c0f6 /arch/arm64/include/asm/processor.h | |
| parent | 99426e5e8c9f11b9de65e7c1200868e8a9ceaa47 (diff) | |
| download | linux-90ec95cda91a021d82351c976896a63aa364ebf1.tar.xz | |
arm64: mm: Introduce VA_BITS_MIN
In order to support 52-bit kernel addresses detectable at boot time, the
kernel needs to know the most conservative VA_BITS possible should it
need to fall back to this quantity due to lack of hardware support.
A new compile time constant VA_BITS_MIN is introduced in this patch and
it is employed in the KASAN end address, KASLR, and EFI stub.
For Arm, if 52-bit VA support is unavailable the fallback is to 48-bits.
In other words: VA_BITS_MIN = min (48, VA_BITS)
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/processor.h')
| -rw-r--r-- | arch/arm64/include/asm/processor.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 844e2964b0f5..0e1f2770192a 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -42,7 +42,7 @@ * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area. */ -#define DEFAULT_MAP_WINDOW_64 (UL(1) << VA_BITS) +#define DEFAULT_MAP_WINDOW_64 (UL(1) << VA_BITS_MIN) #define TASK_SIZE_64 (UL(1) << vabits_user) #ifdef CONFIG_COMPAT |