diff options
| author | Steve Capper <steve.capper@arm.com> | 2019-08-07 16:55:17 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2019-08-09 11:17:16 +0100 |
| commit | 90ec95cda91a021d82351c976896a63aa364ebf1 (patch) | |
| tree | 6f5295463a65f0cda5e79bd47998ab10df11c0f6 /arch/arm64/include/asm | |
| parent | 99426e5e8c9f11b9de65e7c1200868e8a9ceaa47 (diff) | |
| download | linux-90ec95cda91a021d82351c976896a63aa364ebf1.tar.bz2 | |
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')
| -rw-r--r-- | arch/arm64/include/asm/efi.h | 4 | ||||
| -rw-r--r-- | arch/arm64/include/asm/memory.h | 9 | ||||
| -rw-r--r-- | arch/arm64/include/asm/processor.h | 2 |
3 files changed, 11 insertions, 4 deletions
diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h index 76a144702586..b54d3a86c444 100644 --- a/arch/arm64/include/asm/efi.h +++ b/arch/arm64/include/asm/efi.h @@ -79,7 +79,7 @@ static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) /* * On arm64, we have to ensure that the initrd ends up in the linear region, - * which is a 1 GB aligned region of size '1UL << (VA_BITS - 1)' that is + * which is a 1 GB aligned region of size '1UL << (VA_BITS_MIN - 1)' that is * guaranteed to cover the kernel Image. * * Since the EFI stub is part of the kernel Image, we can relax the @@ -90,7 +90,7 @@ static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base) static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, unsigned long image_addr) { - return (image_addr & ~(SZ_1G - 1UL)) + (1UL << (VA_BITS - 1)); + return (image_addr & ~(SZ_1G - 1UL)) + (1UL << (VA_BITS_MIN - 1)); } #define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__) diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 968659c90f5c..79e75e45d560 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -52,6 +52,13 @@ #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) +#if VA_BITS > 48 +#define VA_BITS_MIN (48) +#else +#define VA_BITS_MIN (VA_BITS) +#endif +#define _VA_START(va) (UL(0xffffffffffffffff) - \ + (UL(1) << ((va) - 1)) + 1) #define KERNEL_START _text #define KERNEL_END _end @@ -74,7 +81,7 @@ #define KASAN_THREAD_SHIFT 1 #else #define KASAN_THREAD_SHIFT 0 -#define KASAN_SHADOW_END (VA_START) +#define KASAN_SHADOW_END (_VA_START(VA_BITS_MIN)) #endif #define MIN_THREAD_SHIFT (14 + KASAN_THREAD_SHIFT) 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 |