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author | Mark Rutland <mark.rutland@arm.com> | 2020-11-03 13:22:29 +0300 |
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committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-11-10 20:30:40 +0300 |
commit | 833be850f1cabd0e3b5337c0fcab20a6e936dd48 (patch) | |
tree | f19034fb5146f82b4fc2944ec86fef62581335aa /arch/arm64/include/asm/kernel-pgtable.h | |
parent | ba090f9cafd53dbabe0f0a8c4ccae44203d3731b (diff) | |
download | linux-833be850f1cabd0e3b5337c0fcab20a6e936dd48.tar.xz |
arm64: consistently use reserved_pg_dir
Depending on configuration options and specific code paths, we either
use the empty_zero_page or the configuration-dependent reserved_ttbr0
as a reserved value for TTBR{0,1}_EL1.
To simplify this code, let's always allocate and use the same
reserved_pg_dir, replacing reserved_ttbr0. Note that this is allocated
(and hence pre-zeroed), and is also marked as read-only in the kernel
Image mapping.
Keeping this separate from the empty_zero_page potentially helps with
robustness as the empty_zero_page is used in a number of cases where a
failure to map it read-only could allow it to become corrupted.
The (presently unused) swapper_pg_end symbol is also removed, and
comments are added wherever we rely on the offsets between the
pre-allocated pg_dirs to keep these cases easily identifiable.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201103102229.8542-1-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/include/asm/kernel-pgtable.h')
-rw-r--r-- | arch/arm64/include/asm/kernel-pgtable.h | 6 |
1 files changed, 0 insertions, 6 deletions
diff --git a/arch/arm64/include/asm/kernel-pgtable.h b/arch/arm64/include/asm/kernel-pgtable.h index 19ca76ea60d9..587c504a4c8b 100644 --- a/arch/arm64/include/asm/kernel-pgtable.h +++ b/arch/arm64/include/asm/kernel-pgtable.h @@ -89,12 +89,6 @@ #define INIT_DIR_SIZE (PAGE_SIZE * EARLY_PAGES(KIMAGE_VADDR, _end)) #define IDMAP_DIR_SIZE (IDMAP_PGTABLE_LEVELS * PAGE_SIZE) -#ifdef CONFIG_ARM64_SW_TTBR0_PAN -#define RESERVED_TTBR0_SIZE (PAGE_SIZE) -#else -#define RESERVED_TTBR0_SIZE (0) -#endif - /* Initial memory map size */ #if ARM64_SWAPPER_USES_SECTION_MAPS #define SWAPPER_BLOCK_SHIFT SECTION_SHIFT |