From patchwork Thu Mar 25 13:15:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miaohe Lin X-Patchwork-Id: 12164095 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,URIBL_BLOCKED,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 DB3B9C433E0 for ; Thu, 25 Mar 2021 13:16:40 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 81F6161A1B for ; Thu, 25 Mar 2021 13:16:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 81F6161A1B 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 82EE06B0074; Thu, 25 Mar 2021 09:16:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 768B56B0075; Thu, 25 Mar 2021 09:16:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6309C6B0078; Thu, 25 Mar 2021 09:16:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0138.hostedemail.com [216.40.44.138]) by kanga.kvack.org (Postfix) with ESMTP id 47ADB6B0074 for ; Thu, 25 Mar 2021 09:16:37 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 0593C184D7FA2 for ; Thu, 25 Mar 2021 13:16:37 +0000 (UTC) X-FDA: 77958446034.14.67AA93D Received: from szxga06-in.huawei.com (szxga06-in.huawei.com [45.249.212.32]) by imf06.hostedemail.com (Postfix) with ESMTP id 8C3CEC000C7E for ; Thu, 25 Mar 2021 13:16:35 +0000 (UTC) Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4F5ltz6GJGzkfcn; Thu, 25 Mar 2021 21:14:35 +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; Thu, 25 Mar 2021 21:16:03 +0800 From: Miaohe Lin To: CC: , , , , , , , Subject: [PATCH v3 3/5] mm/migrate.c: fix potential indeterminate pte entry in migrate_vma_insert_page() Date: Thu, 25 Mar 2021 09:15:22 -0400 Message-ID: <20210325131524.48181-4-linmiaohe@huawei.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20210325131524.48181-1-linmiaohe@huawei.com> References: <20210325131524.48181-1-linmiaohe@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.104.175] X-CFilter-Loop: Reflected X-Stat-Signature: mpm7u7aefrgwn1ffz38uzd79mi8kfe9h X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 8C3CEC000C7E Received-SPF: none (huawei.com>: No applicable sender policy available) receiver=imf06; identity=mailfrom; envelope-from=""; helo=szxga06-in.huawei.com; client-ip=45.249.212.32 X-HE-DKIM-Result: none/none X-HE-Tag: 1616678195-735437 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 Reviewed-by: David Hildenbrand --- mm/migrate.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/mm/migrate.c b/mm/migrate.c index dacbdc9710ac..87bbad578127 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2968,6 +2968,13 @@ 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);