From c65e774fb3f6af212641538694b9778ff9ab4300 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Wed, 14 Feb 2018 14:16:53 +0300 Subject: x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable For boot-time switching between 4- and 5-level paging we need to be able to fold p4d page table level at runtime. It requires variable PGDIR_SHIFT and PTRS_PER_P4D. The change doesn't affect the kernel image size much: text data bss dec hex filename 8628091 4734304 1368064 14730459 e0c4db vmlinux.before 8628393 4734340 1368064 14730797 e0c62d vmlinux.after Signed-off-by: Kirill A. Shutemov Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20180214111656.88514-7-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar --- mm/kasan/kasan_init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm/kasan') diff --git a/mm/kasan/kasan_init.c b/mm/kasan/kasan_init.c index 554e4c0f23a2..f436246ccc79 100644 --- a/mm/kasan/kasan_init.c +++ b/mm/kasan/kasan_init.c @@ -31,7 +31,7 @@ unsigned char kasan_zero_page[PAGE_SIZE] __page_aligned_bss; #if CONFIG_PGTABLE_LEVELS > 4 -p4d_t kasan_zero_p4d[PTRS_PER_P4D] __page_aligned_bss; +p4d_t kasan_zero_p4d[MAX_PTRS_PER_P4D] __page_aligned_bss; #endif #if CONFIG_PGTABLE_LEVELS > 3 pud_t kasan_zero_pud[PTRS_PER_PUD] __page_aligned_bss; -- cgit v1.2.3