From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754909AbaEMXhK (ORCPT ); Tue, 13 May 2014 19:37:10 -0400 Received: from terminus.zytor.com ([198.137.202.10]:48055 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752928AbaEMXhG (ORCPT ); Tue, 13 May 2014 19:37:06 -0400 Date: Tue, 13 May 2014 16:36:39 -0700 From: tip-bot for Anthony Iliopoulos Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, dave.hansen@intel.com, shay.goikhman@huawei.com, tglx@linutronix.de, anthony.iliopoulos@huawei.com, hpa@linux.intel.com Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, dave.hansen@intel.com, shay.goikhman@huawei.com, tglx@linutronix.de, anthony.iliopoulos@huawei.com, hpa@linux.intel.com In-Reply-To: <20140514092948.GA17391@server-36.huawei.corp> References: <20140514092948.GA17391@server-36.huawei.corp> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/urgent] x86, mm, hugetlb: Add missing TLB page invalidation for hugetlb_cow() Git-Commit-ID: 9844f5462392b53824e8b86726e7c33b5ecbb676 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 9844f5462392b53824e8b86726e7c33b5ecbb676 Gitweb: http://git.kernel.org/tip/9844f5462392b53824e8b86726e7c33b5ecbb676 Author: Anthony Iliopoulos AuthorDate: Wed, 14 May 2014 11:29:48 +0200 Committer: H. Peter Anvin CommitDate: Tue, 13 May 2014 16:34:09 -0700 x86, mm, hugetlb: Add missing TLB page invalidation for hugetlb_cow() 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 Cc: # v2.6.16+ (!) --- 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 a809121..68c0539 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)