From patchwork Tue Mar 23 13:54:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miaohe Lin X-Patchwork-Id: 12158039 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 8902DC433C1 for ; Tue, 23 Mar 2021 13:54:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1EC4461994 for ; Tue, 23 Mar 2021 13:54:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1EC4461994 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id CF37D6B0145; Tue, 23 Mar 2021 09:54:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C913C6B014A; Tue, 23 Mar 2021 09:54:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B80796B014E; Tue, 23 Mar 2021 09:54:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0205.hostedemail.com [216.40.44.205]) by kanga.kvack.org (Postfix) with ESMTP id 9304D6B014A for ; Tue, 23 Mar 2021 09:54:57 -0400 (EDT) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 5075718042E26 for ; Tue, 23 Mar 2021 13:54:57 +0000 (UTC) X-FDA: 77951285034.18.E095D3A Received: from szxga04-in.huawei.com (szxga04-in.huawei.com [45.249.212.190]) by imf05.hostedemail.com (Postfix) with ESMTP id 06A3BE0011E6 for ; Tue, 23 Mar 2021 13:54:55 +0000 (UTC) Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4F4Xr51pwNz19HCB; Tue, 23 Mar 2021 21:52:53 +0800 (CST) Received: from huawei.com (10.175.104.175) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.498.0; Tue, 23 Mar 2021 21:54:44 +0800 From: Miaohe Lin To: CC: , , , , , , , Subject: [PATCH v2 3/5] mm/migrate.c: fix potential indeterminate pte entry in migrate_vma_insert_page() Date: Tue, 23 Mar 2021 09:54:03 -0400 Message-ID: <20210323135405.65059-4-linmiaohe@huawei.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20210323135405.65059-1-linmiaohe@huawei.com> References: <20210323135405.65059-1-linmiaohe@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.104.175] X-CFilter-Loop: Reflected X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 06A3BE0011E6 X-Stat-Signature: z9otr8juu169ccowtge69uaxhxyx7cxa Received-SPF: none (huawei.com>: No applicable sender policy available) receiver=imf05; identity=mailfrom; envelope-from=""; helo=szxga04-in.huawei.com; client-ip=45.249.212.190 X-HE-DKIM-Result: none/none X-HE-Tag: 1616507695-563280 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: If the zone device page does not belong to un-addressable device memory, the variable entry will be uninitialized and lead to indeterminate pte entry ultimately. Fix this unexpected case and warn about it. Fixes: df6ad69838fc ("mm/device-public-memory: device memory cache coherent with CPU") Signed-off-by: Miaohe Lin --- mm/migrate.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/mm/migrate.c b/mm/migrate.c index 97da1fabdf72..d372be3da9b2 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2972,6 +2972,13 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate, swp_entry = make_device_private_entry(page, vma->vm_flags & VM_WRITE); entry = swp_entry_to_pte(swp_entry); + } else { + /* + * For now we only support migrating to un-addressable + * device memory. + */ + pr_warn_once("Unsupported ZONE_DEVICE page type.\n"); + goto abort; } } else { entry = mk_pte(page, vma->vm_page_prot);