diff options
Diffstat (limited to 'arch/arm64/mm')
| -rw-r--r-- | arch/arm64/mm/mmu.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 6cafd8723d1a..df377fbe464e 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -372,16 +372,28 @@ static void __init __map_memblock(pgd_t *pgd, phys_addr_t start, phys_addr_t end debug_pagealloc_enabled()); /* - * Map the linear alias of the [_text, __init_begin) interval as - * read-only/non-executable. This makes the contents of the - * region accessible to subsystems such as hibernate, but - * protects it from inadvertent modification or execution. + * Map the linear alias of the [_text, __init_begin) interval + * as non-executable now, and remove the write permission in + * mark_linear_text_alias_ro() below (which will be called after + * alternative patching has completed). This makes the contents + * of the region accessible to subsystems such as hibernate, + * but protects it from inadvertent modification or execution. */ __create_pgd_mapping(pgd, kernel_start, __phys_to_virt(kernel_start), - kernel_end - kernel_start, PAGE_KERNEL_RO, + kernel_end - kernel_start, PAGE_KERNEL, early_pgtable_alloc, debug_pagealloc_enabled()); } +void __init mark_linear_text_alias_ro(void) +{ + /* + * Remove the write permissions from the linear alias of .text/.rodata + */ + update_mapping_prot(__pa_symbol(_text), (unsigned long)lm_alias(_text), + (unsigned long)__init_begin - (unsigned long)_text, + PAGE_KERNEL_RO); +} + static void __init map_mem(pgd_t *pgd) { struct memblock_region *reg; |