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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 B3B35C43460 for ; Wed, 5 May 2021 01:37:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9702561029 for ; Wed, 5 May 2021 01:37:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231925AbhEEBiG (ORCPT ); Tue, 4 May 2021 21:38:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:41112 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231459AbhEEBiG (ORCPT ); Tue, 4 May 2021 21:38:06 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 94507610A1; Wed, 5 May 2021 01:37:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1620178630; bh=oA3IsigLUkFUxEgNKlUCMt301JlR4tr4UAaxIQTTqb8=; h=Date:From:To:Subject:In-Reply-To:From; b=CdQMXsNEMMMwATto74sZZA4MCmuge1l4OkRUvTPClkY3sZdUmL3b6I5LYfgZYUOHT pXeB+GWEc6YscdgAi9HZ4/f+sjZaTI/kZaTi2AUjQvOjABxO/bwJSVGxa+s1hmReqZ tqdSOmIBln23JqAbpIcuz231JiLnIcOJT+ikyB9k= Date: Tue, 04 May 2021 18:37:10 -0700 From: Andrew Morton To: akpm@linux-foundation.org, apopple@nvidia.com, aquini@redhat.com, david@redhat.com, jglisse@redhat.com, linmiaohe@huawei.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, shy828301@gmail.com, torvalds@linux-foundation.org Subject: [patch 082/143] mm/migrate.c: fix potential indeterminate pte entry in migrate_vma_insert_page() Message-ID: <20210505013710.tBHbfbSFt%akpm@linux-foundation.org> In-Reply-To: <20210504183219.a3cc46aee4013d77402276c5@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Miaohe Lin Subject: mm/migrate.c: fix potential indeterminate pte entry in migrate_vma_insert_page() 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. Link: https://lkml.kernel.org/r/20210325131524.48181-4-linmiaohe@huawei.com Fixes: df6ad69838fc ("mm/device-public-memory: device memory cache coherent with CPU") Signed-off-by: Miaohe Lin Reviewed-by: David Hildenbrand Cc: Alistair Popple Cc: Jerome Glisse Cc: Rafael Aquini Cc: Yang Shi Signed-off-by: Andrew Morton --- mm/migrate.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/mm/migrate.c~mm-migratec-fix-potential-indeterminate-pte-entry-in-migrate_vma_insert_page +++ a/mm/migrate.c @@ -2947,6 +2947,13 @@ static void migrate_vma_insert_page(stru 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); _