Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1768835Ab2KOT2F (ORCPT ); Thu, 15 Nov 2012 14:28:05 -0500 Received: from mga09.intel.com ([134.134.136.24]:65277 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1768765Ab2KOTZ7 (ORCPT ); Thu, 15 Nov 2012 14:25:59 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.83,259,1352102400"; d="scan'208";a="242837199" From: "Kirill A. Shutemov" To: Andrew Morton , Andrea Arcangeli , linux-mm@kvack.org Cc: Andi Kleen , "H. Peter Anvin" , linux-kernel@vger.kernel.org, "Kirill A. Shutemov" , David Rientjes , "Kirill A. Shutemov" Subject: [PATCH v6 05/12] thp: change_huge_pmd(): keep huge zero page write-protected Date: Thu, 15 Nov 2012 21:26:55 +0200 Message-Id: <1353007622-18393-6-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1353007622-18393-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1353007622-18393-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1018 Lines: 31 From: "Kirill A. Shutemov" We want to get page fault on write attempt to huge zero page, so let's keep it write-protected. Signed-off-by: Kirill A. Shutemov --- mm/huge_memory.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index f5589c0..42607a1 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1245,6 +1245,8 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, pmd_t entry; entry = pmdp_get_and_clear(mm, addr, pmd); entry = pmd_modify(entry, newprot); + if (is_huge_zero_pmd(entry)) + entry = pmd_wrprotect(entry); set_pmd_at(mm, addr, pmd, entry); spin_unlock(&vma->vm_mm->page_table_lock); ret = 1; -- 1.7.11.7 -- 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/