From patchwork Thu Jun 10 11:24:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhang Yi X-Patchwork-Id: 12312707 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=-11.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,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 B47A4C48BDF for ; Thu, 10 Jun 2021 11:15:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9469F613F5 for ; Thu, 10 Jun 2021 11:15:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230188AbhFJLRs (ORCPT ); Thu, 10 Jun 2021 07:17:48 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:9066 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229961AbhFJLRs (ORCPT ); Thu, 10 Jun 2021 07:17:48 -0400 Received: from dggeme752-chm.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4G11Y750PlzYsRj; Thu, 10 Jun 2021 19:12:59 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggeme752-chm.china.huawei.com (10.3.19.98) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Thu, 10 Jun 2021 19:15:50 +0800 From: Zhang Yi To: , , , CC: , , , Subject: [RFC PATCH v4 0/8] ext4, jbd2: fix 3 issues about bdev_try_to_free_page() Date: Thu, 10 Jun 2021 19:24:32 +0800 Message-ID: <20210610112440.3438139-1-yi.zhang@huawei.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggeme752-chm.china.huawei.com (10.3.19.98) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This patchset fix a potential filesystem inconsistency problem and two use-after-free problems about bdev_try_to_free_page(). Patch 1-4: Fix a potential filesystem inconsistency problem caused by freeing buffers and doing umount concurrently, and also do some cleanup. Patch 5-8: Add a shrinker to release journal_head of checkpoint buffers and remove the buggy bdev_try_to_free_page() at all. Changes since v3: - Patch 2: Fix one spelling mistake. - Patch 3: Drop unnecessary 'result' check codes. - Patch 5, declare static for jbd2_journal_shrink_[scan|count](), and use percpu_counter_read_positive() to calculate the number of shrinkable journal heads. - Add 'Reviewed-by' tag from Jan besides the fifth patch. Hi Jan, I modify the fifth patch as Dave suggested, please give a look at this patch again. Thanks, Yi. ------------------ Changes since v2: - Fix some comments and spelling mistakes on patch 2 and 3. - Give up the solution of add refcount on super_block and fix the use-after-free issue in bdev_try_to_free_page(), switch to introduce a shrinker to free checkpoint buffers' journal_head and remove the whole callback at all. Changes since v1: - Do not use j_checkpoint_mutex to fix the filesystem inconsistency problem, introduce a new mark instead. - Fix superblock use-after-free issue in blkdev_releasepage(). - Avoid race between bdev_try_to_free_page() and ext4_put_super(). Zhang Yi (8): jbd2: remove the out label in __jbd2_journal_remove_checkpoint() jbd2: ensure abort the journal if detect IO error when writing original buffer back jbd2: don't abort the journal when freeing buffers jbd2: remove redundant buffer io error checks jbd2,ext4: add a shrinker to release checkpointed buffers jbd2: simplify journal_clean_one_cp_list() ext4: remove bdev_try_to_free_page() callback fs: remove bdev_try_to_free_page callback fs/block_dev.c | 15 --- fs/ext4/super.c | 29 ++--- fs/jbd2/checkpoint.c | 206 +++++++++++++++++++++++++++++------- fs/jbd2/journal.c | 101 ++++++++++++++++++ fs/jbd2/transaction.c | 17 --- include/linux/fs.h | 1 - include/linux/jbd2.h | 37 +++++++ include/trace/events/jbd2.h | 101 ++++++++++++++++++ 8 files changed, 414 insertions(+), 93 deletions(-) Reviewed-by: Christoph Hellwig