From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx> The __Pxxx/__Sxxx macros are only for init protection_map[]. All usage of them in linux should come from protection_map array. Becasue a lot of architectures would re-initilize protection_map[] array, eg: x86-mem_encrypt, m68k-motorola, mips, arm, sparc. Using __P000 maybe won't cause bug because hw would deny access with PROT_NONE permission, but it's not rigorous. Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/debug_vm_pgtable.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index 1403639302e4..a6ebbf6e53dd 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -1104,13 +1104,13 @@ static int __init init_args(struct pgtable_debug_args *args) /* * Initialize the debugging data. * - * __P000 (or even __S000) will help create page table entries with + * __P000 (protection_map[0]) will help create page table entries with * PROT_NONE permission as required for pxx_protnone_tests(). */ memset(args, 0, sizeof(*args)); args->vaddr = get_random_vaddr(); args->page_prot = vm_get_page_prot(VMFLAGS); - args->page_prot_none = __P000; + args->page_prot_none = protection_map[0]; args->is_contiguous_page = false; args->pud_pfn = ULONG_MAX; args->pmd_pfn = ULONG_MAX; -- 2.25.1
