From patchwork Wed Oct 6 02:18:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rongwei Wang X-Patchwork-Id: 12538359 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1AECFC433EF for ; Wed, 6 Oct 2021 02:18:50 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id CB0B561207 for ; Wed, 6 Oct 2021 02:18:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org CB0B561207 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 170F76B0071; Tue, 5 Oct 2021 22:18:46 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 121276B0074; Tue, 5 Oct 2021 22:18:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EE2B16B0075; Tue, 5 Oct 2021 22:18:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0123.hostedemail.com [216.40.44.123]) by kanga.kvack.org (Postfix) with ESMTP id D5BE66B0074 for ; Tue, 5 Oct 2021 22:18:45 -0400 (EDT) Received: from smtpin40.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 99D7718141EFD for ; Wed, 6 Oct 2021 02:18:45 +0000 (UTC) X-FDA: 78664404210.40.F11990A Received: from out30-42.freemail.mail.aliyun.com (out30-42.freemail.mail.aliyun.com [115.124.30.42]) by imf05.hostedemail.com (Postfix) with ESMTP id CF7E75077FB3 for ; Wed, 6 Oct 2021 02:18:44 +0000 (UTC) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R901e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04357;MF=rongwei.wang@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0Uqi9lTZ_1633486717; Received: from localhost.localdomain(mailfrom:rongwei.wang@linux.alibaba.com fp:SMTPD_---0Uqi9lTZ_1633486717) by smtp.aliyun-inc.com(127.0.0.1); Wed, 06 Oct 2021 10:18:38 +0800 From: Rongwei Wang To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: akpm@linux-foundation.org, willy@infradead.org, song@kernel.org, william.kucharski@oracle.com, hughd@google.com Subject: [PATCH v3 v3 0/2] mm, thp: fix file-backed THP race in collapse_file and truncate pagecache Date: Wed, 6 Oct 2021 10:18:35 +0800 Message-Id: <20211006021837.59721-1-rongwei.wang@linux.alibaba.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210906121200.57905-1-rongwei.wang@linux.alibaba.com> References: <20210906121200.57905-1-rongwei.wang@linux.alibaba.com> MIME-Version: 1.0 X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: CF7E75077FB3 X-Stat-Signature: t9feoio6efmiew3h8aopws94umwuyi1g Authentication-Results: imf05.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=alibaba.com; spf=pass (imf05.hostedemail.com: domain of rongwei.wang@linux.alibaba.com designates 115.124.30.42 as permitted sender) smtp.mailfrom=rongwei.wang@linux.alibaba.com X-HE-Tag: 1633486724-417985 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: Hi, We found two bugs related to file-backed THP in our cases, recently. The two bugs rough description as following: 1. in truncate_inode_pages_range, subpage(s) of file-backed THP can be revealed by find_get_entry. 2. 'collapse_file' miss the pages which in writeback but no private. This situation will be triggered in XFS when block size is set to PAGESIZE. These two patches mainly fix the above mentioned bugs, and have been tested in latest branch. Changelog: v2 -> v3: - Patch "mm, thp: lock filemap when truncating page cache" add filemap_invalidate_{un}lock before and after calling truncate_pagecache (Suggested by Song Liu and Matthew). v1 -> v2: - Patch "mm, thp: check page mapping when truncating page cache" move the check of page mapping to behind lock_page. - Patch "mm, thp: bail out early in collapse_file for writeback page" check the writeback flag before taking page lock (Suggested by Yang Shi). v1 link: https://patchwork.kernel.org/project/linux-mm/cover/20210906121200.57905-1-rongwei.wang@linux.alibaba.com/ v2 link: https://patchwork.kernel.org/project/linux-mm/patch/20210922070645.47345-2-rongwei.wang@linux.alibaba.com/ Rongwei Wang (2): mm, thp: lock filemap when truncating page cache mm, thp: bail out early in collapse_file for writeback page fs/open.c | 5 ++++- mm/khugepaged.c | 7 ++++++- 2 files changed, 10 insertions(+), 2 deletions(-)