From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3E2C3C4CEC7 for ; Fri, 13 Sep 2019 16:32:59 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 15203208C2 for ; Fri, 13 Sep 2019 16:32:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="A+hoQL5F" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 15203208C2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Owner; bh=aCRXXXaep5z0ug8GGUWXUtNsEWhlJdXprv0EmVG7z38=; b=A+h oQL5FJqGD7O32IZViZVaTsQfDXxOyLcPhcs3+sQ0C2NGhA/B1FoiISfEQ/ViEOuvHNNJye3l1QYaZ w2HFYIJo0c452DrDzkg1lHkwDuSeVZkXik7gA9QYhnylKdzzvQ7O58geLeAhelsYFH+xUeigQAwwN 61upn8N+f6cQKo1JC6YmKkDlxN7hYfGF4+MJWg6iYoElkIPu7qLDuIeScl0HwPi0KdF14458hzXKZ txoleVgH5HKkov5f4POMKdSCSoO1JKA5jU0WXvlcpWlwCIxOw0iQ/2YhA3JMemsi8Ap2ANvV+zR5Z Aa0VvNtgaBTnXD3InybJkcV6ODiYMCw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1i8oVG-00057V-I0; Fri, 13 Sep 2019 16:32:58 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1i8oVD-00056p-M5 for linux-arm-kernel@lists.infradead.org; Fri, 13 Sep 2019 16:32:56 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 72A141000; Fri, 13 Sep 2019 09:32:52 -0700 (PDT) Received: from localhost.localdomain (entos-thunderx2-02.shanghai.arm.com [10.169.40.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id DF2B53F67D; Fri, 13 Sep 2019 09:32:47 -0700 (PDT) From: Jia He To: Catalin Marinas , Will Deacon , Mark Rutland , James Morse , Marc Zyngier , Matthew Wilcox , "Kirill A. Shutemov" , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v3 0/2] fix double page fault on arm64 Date: Sat, 14 Sep 2019 00:32:37 +0800 Message-Id: <20190913163239.125108-1-justin.he@arm.com> X-Mailer: git-send-email 2.17.1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190913_093255_767689_3DC4F37F X-CRM114-Status: UNSURE ( 9.54 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ralph Campbell , Jia He , Andrew Morton , Anshuman Khandual , Jun Yao , =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Punit Agrawal , hejianet@gmail.com, Thomas Gleixner , Robin Murphy , Alex Van Brunt MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org When we tested pmdk unit test vmmalloc_fork TEST1 in arm64 guest, there will be a double page fault in __copy_from_user_inatomic of cow_user_page. As told by Catalin: "On arm64 without hardware Access Flag, copying from user will fail because the pte is old and cannot be marked young. So we always end up with zeroed page after fork() + CoW for pfn mappings. we don't always have a hardware-managed access flag on arm64." Changes v3: add vmf->ptl lock/unlock (by Kirill A. Shutemov) add arch_faults_on_old_pte (Matthew, Catalins) v2: remove FAULT_FLAG_WRITE when setting pte access flag (by Catalin) Jia He (2): arm64: mm: implement arch_faults_on_old_pte() on arm64 mm: fix double page fault on arm64 if PTE_AF is cleared arch/arm64/include/asm/pgtable.h | 11 +++++++++++ mm/memory.c | 29 ++++++++++++++++++++++++----- 2 files changed, 35 insertions(+), 5 deletions(-) -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel