Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936530AbaFIJan (ORCPT ); Mon, 9 Jun 2014 05:30:43 -0400 Received: from ip4-83-240-18-248.cust.nbox.cz ([83.240.18.248]:59137 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936371AbaFIJ11 (ORCPT ); Mon, 9 Jun 2014 05:27:27 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Anthony Iliopoulos , "H. Peter Anvin" , Jiri Slaby Subject: [PATCH 3.12 030/146] x86, mm, hugetlb: Add missing TLB page invalidation for hugetlb_cow() Date: Mon, 9 Jun 2014 10:49:25 +0200 Message-Id: <09a5e7771d3dbbb1cee730688da3f1d0830495d3.1402303820.git.jslaby@suse.cz> X-Mailer: git-send-email 1.9.3 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Anthony Iliopoulos 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 9844f5462392b53824e8b86726e7c33b5ecbb676 upstream. The invalidation is required in order to maintain proper semantics under CoW conditions. In scenarios where a process clones several threads, a thread operating on a core whose DTLB entry for a particular hugepage has not been invalidated, will be reading from the hugepage that belongs to the forked child process, even after hugetlb_cow(). The thread will not see the updated page as long as the stale DTLB entry remains cached, the thread attempts to write into the page, the child process exits, or the thread gets migrated to a different processor. Signed-off-by: Anthony Iliopoulos Link: http://lkml.kernel.org/r/20140514092948.GA17391@server-36.huawei.corp Suggested-by: Shay Goikhman Acked-by: Dave Hansen Signed-off-by: H. Peter Anvin Signed-off-by: Jiri Slaby --- arch/x86/include/asm/hugetlb.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h index a8091216963b..68c05398bba9 100644 --- a/arch/x86/include/asm/hugetlb.h +++ b/arch/x86/include/asm/hugetlb.h @@ -52,6 +52,7 @@ static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm, static inline void huge_ptep_clear_flush(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) { + ptep_clear_flush(vma, addr, ptep); } static inline int huge_pte_none(pte_t pte) -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/