From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f198.google.com (mail-pf0-f198.google.com [209.85.192.198]) by kanga.kvack.org (Postfix) with ESMTP id 6F1916B0290 for ; Mon, 26 Dec 2016 20:55:44 -0500 (EST) Received: by mail-pf0-f198.google.com with SMTP id y68so500716868pfb.6 for ; Mon, 26 Dec 2016 17:55:44 -0800 (PST) Received: from mga14.intel.com (mga14.intel.com. [192.55.52.115]) by mx.google.com with ESMTPS id j186si44800953pfb.193.2016.12.26.17.55.43 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 26 Dec 2016 17:55:43 -0800 (PST) From: "Kirill A. Shutemov" Subject: [PATCHv2 12/29] x86/mm: add support of p4d_t in vmalloc_fault() Date: Tue, 27 Dec 2016 04:53:56 +0300 Message-Id: <20161227015413.187403-13-kirill.shutemov@linux.intel.com> In-Reply-To: <20161227015413.187403-1-kirill.shutemov@linux.intel.com> References: <20161227015413.187403-1-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Linus Torvalds , Andrew Morton , x86@kernel.org, Thomas Gleixner , Ingo Molnar , Arnd Bergmann , "H. Peter Anvin" Cc: Andi Kleen , Dave Hansen , Andy Lutomirski , linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" With 4-level paging copying happens on p4d level, as we have pgd_none() always false when p4d_t folded. Signed-off-by: Kirill A. Shutemov --- arch/x86/mm/fault.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 59104b78e8a7..b4bcf2dac4a9 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -434,6 +434,7 @@ void vmalloc_sync_all(void) static noinline int vmalloc_fault(unsigned long address) { pgd_t *pgd, *pgd_ref; + p4d_t *p4d, *p4d_ref; pud_t *pud, *pud_ref; pmd_t *pmd, *pmd_ref; pte_t *pte, *pte_ref; @@ -461,13 +462,26 @@ static noinline int vmalloc_fault(unsigned long address) BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref)); } + /* With 4-level paging copying happens on p4d level. */ + p4d = p4d_offset(pgd, address); + p4d_ref = p4d_offset(pgd_ref, address); + if (p4d_none(*p4d_ref)) + return -1; + + if (p4d_none(*p4d)) { + set_p4d(p4d, *p4d_ref); + arch_flush_lazy_mmu_mode(); + } else { + BUG_ON(p4d_pfn(*p4d) != p4d_pfn(*p4d_ref)); + } + /* * Below here mismatches are bugs because these lower tables * are shared: */ - pud = pud_offset(pgd, address); - pud_ref = pud_offset(pgd_ref, address); + pud = pud_offset(p4d, address); + pud_ref = pud_offset(p4d_ref, address); if (pud_none(*pud_ref)) return -1; -- 2.11.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org