On Thu, Aug 22, 2024 at 02:15:17AM +0100, Mark Brown wrote:
diff --git a/arch/arm64/include/asm/mman.h b/arch/arm64/include/asm/mman.h index c21849ffdd88..37dfd2882f04 100644 --- a/arch/arm64/include/asm/mman.h +++ b/arch/arm64/include/asm/mman.h @@ -61,6 +61,15 @@ static inline bool arch_validate_flags(unsigned long vm_flags) return false; }
- if (system_supports_gcs() && (vm_flags & VM_SHADOW_STACK)) {
/* An executable GCS isn't a good idea. */if (vm_flags & VM_EXEC)return false;
Later we should look at clear VM_MAYEXEC in the core code (if the x86 folk agree).
/* The memory management core should prevent this */VM_WARN_ON(vm_flags & VM_SHARED);- }
- return true;
} diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c index 642bdf908b22..3ed63fc8cd0a 100644 --- a/arch/arm64/mm/mmap.c +++ b/arch/arm64/mm/mmap.c @@ -83,9 +83,17 @@ arch_initcall(adjust_protection_map); pgprot_t vm_get_page_prot(unsigned long vm_flags) {
- pteval_t prot = pgprot_val(protection_map[vm_flags &
- pteval_t prot;
- /* Short circuit GCS to avoid bloating the table. */
- if (system_supports_gcs() && (vm_flags & VM_SHADOW_STACK)) {
prot = _PAGE_GCS_RO;- } else {
prot = pgprot_val(protection_map[vm_flags & (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]);- }
- /* VM_ARM64_BTI on a GCS is rejected in arch_validate_flags() */
Not anymore.
if (vm_flags & VM_ARM64_BTI) prot |= PTE_GP;
Other than the comment above, it looks good.
Reviewed-by: Catalin Marinas catalin.marinas@arm.com