From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7159E2AE68 for ; Wed, 9 Sep 2026 02:03:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788919434; cv=none; b=KNv0kO52WthyVDUApE+7FpDMvsq6EfwIUgkfLavgPwjNYIgZ9npoEh+1Mhtwd+9uSEWDcOd6uFcihn/dTeKvfMW+UhjhtmbNI3lxdIZPyVeMLcU4aM04HVusCakHCJgOOaFfWcCNUJVL8XgMyQgeVpWOtS8Jq2w2Euf4vy5zApI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788919434; c=relaxed/simple; bh=7QxfwFB1513YCpCcinldL5FCs6fclRFzOy9S2pH6RQ4=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=EngmY1Pc7jGoUEezPkPTx8GFkajDLlYO2XhHrr2leQhSJDU2TB/7mqa0W97HRglmKLUgIcHfqDBt4I6XbYPtMj4n3bk3mTBTY2O2eldqS7ImRfgVwr2vP4DDi0rNDLBgpnEtfpemzFvOWruu25JKPgZnekG3Lpm5bAgXwSujOMA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VYkQ2X/v; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VYkQ2X/v" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1AD4C1F00A3A; Wed, 9 Sep 2026 02:03:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788919433; bh=iPPijrSAEf6GC7mT3EoUKryESek5TYWN+vDTDROlKhQ=; h=Date:Cc:Subject:To:References:From:In-Reply-To; b=VYkQ2X/vI7dLQ0twmWOT67G8W6ceML31Wc8XfnLg4liLyBb0VU+sy+nj5uVRU8K77 U3aACHvERUx6A/7nSEb6JEKZpWpScl3bp7KTekr5HXRt7cfvBlz/YBdAD53+mtY42d vG2hPNfGq0Yxvd4KDexj/MMGwuMR37IcQuDssppNpbjimSqn+jRgkf9Bwj6tmT4FeD YATF9XIsR3/2Ej+pbOycR0mkTFg9kXzRGMR0TCsccroV/00XdIvAAii+BYt+Vk1RFd 8Ilye4FCvOp7wjlVa3Gt0c3Xztl7xNmYfBdHGtd8nN1Q2fIS34/u9Bclx7BXZ28bDD JCS5PFuiNRkZg== Message-ID: Date: Wed, 9 Sep 2026 10:03:50 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: chao@kernel.org, jaegeuk@kernel.org, stable@kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Subject: Re: [f2fs-dev] [PATCH] f2fs: fix to avoid potential deadloop in f2fs_fsync_node_pages() To: Zhiguo Niu References: <20260824131729.3694378-1-chao@kernel.org> Content-Language: en-US From: Chao Yu In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 9/9/26 09:12, Zhiguo Niu wrote: > Chao Yu via Linux-f2fs-devel > 于2026年8月24日周一 21:19写道： >> >> There is potential deadloop in race condition: >> >> Thread A Thread B >> - fsync >> - f2fs_do_sync_file >> - f2fs_fsync_node_pages >> - last_fsync_dnode >> - folio_get(last_folio) >> - f2fs_setattr >> - f2fs_truncate >> - f2fs_truncate_blocks >> - f2fs_do_truncate_blocks >> - f2fs_truncate_inode_blocks >> - truncate_dnode >> - truncate_node >> - invalidate_mapping_pages >> - folio->mapping = NULL >> - is_node_folio alwasy return false >> - atomic && !marked is always true, >> then goto retry >> >> Cc: stable@kernel.org >> Fixes: 608514deba38 ("f2fs: set fsync mark only for the last dnode") >> Signed-off-by: Chao Yu >> --- >> fs/f2fs/node.c | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c >> index 968e5ed38816..86c2e67e43b6 100644 >> --- a/fs/f2fs/node.c >> +++ b/fs/f2fs/node.c >> @@ -2016,6 +2016,11 @@ int f2fs_fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode, >> f2fs_debug(sbi, "Retry to write fsync mark: ino=%u, idx=%lx", >> ino, last_folio->index); >> folio_lock(last_folio); >> + if (unlikely(!is_node_folio(last_folio))) { > Hi Chao, > is_node_folio->NODE_MAPPING(F2FS_F_SB(folio))->F2FS_M_SB(folio->mappping)->F2FS_I_SB(mapping->host) > if mapping==NULL, panic will occur here? > just like commit msg in mai: "f2fs: parameterize node helpers and macros" Hi Zhiguo, Ah, seems we need to revert ("f2fs: introduce is_{meta,node}_folio") which introduce this bug? IIUC. Thanks, > thanks！ > >> + f2fs_folio_put(last_folio, true); >> + ret = -EAGAIN; >> + goto out; >> + } >> f2fs_folio_wait_writeback(last_folio, NODE, true, true); >> folio_mark_dirty(last_folio); >> folio_unlock(last_folio); >> -- >> 2.49.0 >> >> >> >> _______________________________________________ >> Linux-f2fs-devel mailing list >> Linux-f2fs-devel@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel