diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2024-02-14 13:29:04 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2024-02-16 12:42:33 +0000 |
| commit | 97a6f43bb049e64b9913c50c7530e13d78e205d4 (patch) | |
| tree | f27badee5d092ecc09f221e6ce6dd19b83e9b44c /arch/arm64/include/asm | |
| parent | 82ca151da7d54d7571c5d511d016b7780d5d559f (diff) | |
arm64: head: Move early kernel mapping routines into C code
The asm version of the kernel mapping code works fine for creating a
coarse grained identity map, but for mapping the kernel down to its
exact boundaries with the right attributes, it is not suitable. This is
why we create a preliminary RWX kernel mapping first, and then rebuild
it from scratch later on.
So let's reimplement this in C, in a way that will make it unnecessary
to create the kernel page tables yet another time in paging_init().
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20240214122845.2033971-63-ardb+git@google.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/include/asm')
| -rw-r--r-- | arch/arm64/include/asm/archrandom.h | 2 | ||||
| -rw-r--r-- | arch/arm64/include/asm/scs.h | 32 |
2 files changed, 3 insertions, 31 deletions
diff --git a/arch/arm64/include/asm/archrandom.h b/arch/arm64/include/asm/archrandom.h index ecdb3cfcd0f8..8babfbe31f95 100644 --- a/arch/arm64/include/asm/archrandom.h +++ b/arch/arm64/include/asm/archrandom.h @@ -129,6 +129,4 @@ static inline bool __init __early_cpu_has_rndr(void) return (ftr >> ID_AA64ISAR0_EL1_RNDR_SHIFT) & 0xf; } -u64 kaslr_early_init(void *fdt); - #endif /* _ASM_ARCHRANDOM_H */ diff --git a/arch/arm64/include/asm/scs.h b/arch/arm64/include/asm/scs.h index eca2ba5a6276..2e010ea76be2 100644 --- a/arch/arm64/include/asm/scs.h +++ b/arch/arm64/include/asm/scs.h @@ -33,37 +33,11 @@ #include <asm/cpufeature.h> #ifdef CONFIG_UNWIND_PATCH_PAC_INTO_SCS -static inline bool should_patch_pac_into_scs(void) -{ - u64 reg; - - /* - * We only enable the shadow call stack dynamically if we are running - * on a system that does not implement PAC or BTI. PAC and SCS provide - * roughly the same level of protection, and BTI relies on the PACIASP - * instructions serving as landing pads, preventing us from patching - * those instructions into something else. - */ - reg = read_sysreg_s(SYS_ID_AA64ISAR1_EL1); - if (SYS_FIELD_GET(ID_AA64ISAR1_EL1, APA, reg) | - SYS_FIELD_GET(ID_AA64ISAR1_EL1, API, reg)) - return false; - - reg = read_sysreg_s(SYS_ID_AA64ISAR2_EL1); - if (SYS_FIELD_GET(ID_AA64ISAR2_EL1, APA3, reg)) - return false; - - if (IS_ENABLED(CONFIG_ARM64_BTI_KERNEL)) { - reg = read_sysreg_s(SYS_ID_AA64PFR1_EL1); - if (reg & (0xf << ID_AA64PFR1_EL1_BT_SHIFT)) - return false; - } - return true; -} - static inline void dynamic_scs_init(void) { - if (should_patch_pac_into_scs()) { + extern bool __pi_dynamic_scs_is_enabled; + + if (__pi_dynamic_scs_is_enabled) { pr_info("Enabling dynamic shadow call stack\n"); static_branch_enable(&dynamic_scs_enabled); } |