From 91f606a8fa68264224cbc76888fa8649cdbe9990 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Wed, 14 Feb 2018 21:25:41 +0300 Subject: x86/mm: Replace compile-time checks for 5-level paging with runtime-time checks This patch converts the of CONFIG_X86_5LEVEL check to runtime checks for p4d folding. Signed-off-by: Kirill A. Shutemov Cc: Andy Lutomirski Cc: Arjan van de Ven Cc: Borislav Petkov Cc: Dan Williams Cc: Dave Hansen Cc: David Woodhouse Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20180214182542.69302-9-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar --- arch/x86/mm/kaslr.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/x86/mm/kaslr.c') diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 641169d38184..615cc03ced84 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -124,7 +124,7 @@ void __init kernel_randomize_memory(void) */ entropy = remain_entropy / (ARRAY_SIZE(kaslr_regions) - i); prandom_bytes_state(&rand_state, &rand, sizeof(rand)); - if (IS_ENABLED(CONFIG_X86_5LEVEL)) + if (pgtable_l5_enabled) entropy = (rand % (entropy + 1)) & P4D_MASK; else entropy = (rand % (entropy + 1)) & PUD_MASK; @@ -136,7 +136,7 @@ void __init kernel_randomize_memory(void) * randomization alignment. */ vaddr += get_padding(&kaslr_regions[i]); - if (IS_ENABLED(CONFIG_X86_5LEVEL)) + if (pgtable_l5_enabled) vaddr = round_up(vaddr + 1, P4D_SIZE); else vaddr = round_up(vaddr + 1, PUD_SIZE); @@ -212,7 +212,7 @@ void __meminit init_trampoline(void) return; } - if (IS_ENABLED(CONFIG_X86_5LEVEL)) + if (pgtable_l5_enabled) init_trampoline_p4d(); else init_trampoline_pud(); -- cgit