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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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,USER_AGENT_GIT autolearn=unavailable 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 91B54C43381 for ; Tue, 2 Mar 2021 02:28:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6042964DA1 for ; Tue, 2 Mar 2021 02:28:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348812AbhCBBZc (ORCPT ); Mon, 1 Mar 2021 20:25:32 -0500 Received: from mail.kernel.org ([198.145.29.99]:39774 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240447AbhCATK1 (ORCPT ); Mon, 1 Mar 2021 14:10:27 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4F8456535E; Mon, 1 Mar 2021 17:45:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614620754; bh=S+QW9hh9mJ37hBQuOdAPwSZ0vQfS3UapgfeipdWGbzU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=is7OX0lX2RIbWH30nVxxCrWNH0tZmwbQJuQEn8DoY9JK3ypYuteTpyq0dkBo1ZLmO ftWxtZeAmQEF6Oj8QYWfZYCcllHOKJ8ReULHSoe4e3UcVsFxcJqYag5y9FJA2PCVVC U/lIY54OdrNo94I9a/81Rx1/aRIpUL4Z/Me868f4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chao Yu , Jaegeuk Kim , Sasha Levin Subject: [PATCH 5.11 237/775] f2fs: compress: fix potential deadlock Date: Mon, 1 Mar 2021 17:06:45 +0100 Message-Id: <20210301161213.341496022@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161201.679371205@linuxfoundation.org> References: <20210301161201.679371205@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chao Yu [ Upstream commit 3afae09ffea5e08f523823be99a784675995d6bb ] generic/269 reports a hangtask issue, the root cause is ABBA deadlock described as below: Thread A Thread B - down_write(&sbi->gc_lock) -- A - f2fs_write_data_pages - lock all pages in cluster -- B - f2fs_write_multi_pages - f2fs_write_raw_pages - f2fs_write_single_data_page - f2fs_balance_fs - down_write(&sbi->gc_lock) -- A - f2fs_gc - do_garbage_collect - ra_data_block - pagecache_get_page -- B To fix this, it needs to avoid calling f2fs_balance_fs() if there is still cluster pages been locked in context of cluster writeback, so instead, let's call f2fs_balance_fs() in the end of f2fs_write_raw_pages() when all cluster pages were unlocked. Fixes: 4c8ff7095bef ("f2fs: support data compression") Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin --- fs/f2fs/compress.c | 5 ++++- fs/f2fs/data.c | 10 ++++++---- fs/f2fs/f2fs.h | 2 +- 3 files changed, 11 insertions(+), 6 deletions(-) diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c index 4bcbacfe33259..7a774c9e4cb89 100644 --- a/fs/f2fs/compress.c +++ b/fs/f2fs/compress.c @@ -1415,7 +1415,7 @@ retry_write: ret = f2fs_write_single_data_page(cc->rpages[i], &_submitted, NULL, NULL, wbc, io_type, - compr_blocks); + compr_blocks, false); if (ret) { if (ret == AOP_WRITEPAGE_ACTIVATE) { unlock_page(cc->rpages[i]); @@ -1450,6 +1450,9 @@ retry_write: *submitted += _submitted; } + + f2fs_balance_fs(F2FS_M_SB(mapping), true); + return 0; out_err: for (++i; i < cc->cluster_size; i++) { diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index aa34d620bec98..d72c99d9bd1f4 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -2743,7 +2743,8 @@ int f2fs_write_single_data_page(struct page *page, int *submitted, sector_t *last_block, struct writeback_control *wbc, enum iostat_type io_type, - int compr_blocks) + int compr_blocks, + bool allow_balance) { struct inode *inode = page->mapping->host; struct f2fs_sb_info *sbi = F2FS_I_SB(inode); @@ -2881,7 +2882,7 @@ out: } unlock_page(page); if (!S_ISDIR(inode->i_mode) && !IS_NOQUOTA(inode) && - !F2FS_I(inode)->cp_task) + !F2FS_I(inode)->cp_task && allow_balance) f2fs_balance_fs(sbi, need_balance_fs); if (unlikely(f2fs_cp_error(sbi))) { @@ -2928,7 +2929,7 @@ out: #endif return f2fs_write_single_data_page(page, NULL, NULL, NULL, - wbc, FS_DATA_IO, 0); + wbc, FS_DATA_IO, 0, true); } /* @@ -3096,7 +3097,8 @@ continue_unlock: } #endif ret = f2fs_write_single_data_page(page, &submitted, - &bio, &last_block, wbc, io_type, 0); + &bio, &last_block, wbc, io_type, + 0, true); if (ret == AOP_WRITEPAGE_ACTIVATE) unlock_page(page); #ifdef CONFIG_F2FS_FS_COMPRESSION diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index bb11759191dcc..1578402c58444 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -3469,7 +3469,7 @@ int f2fs_write_single_data_page(struct page *page, int *submitted, struct bio **bio, sector_t *last_block, struct writeback_control *wbc, enum iostat_type io_type, - int compr_blocks); + int compr_blocks, bool allow_balance); void f2fs_invalidate_page(struct page *page, unsigned int offset, unsigned int length); int f2fs_release_page(struct page *page, gfp_t wait); -- 2.27.0