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=-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 E9DB6C433E2 for ; Tue, 23 Mar 2021 13:55:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 921FC61994 for ; Tue, 23 Mar 2021 13:55:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231833AbhCWNza (ORCPT ); Tue, 23 Mar 2021 09:55:30 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:14129 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231897AbhCWNyz (ORCPT ); Tue, 23 Mar 2021 09:54:55 -0400 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 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.104.175] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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); -- 2.19.1