From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1A75364A for ; Wed, 10 Apr 2024 01:25:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712712304; cv=none; b=TWu9kvYV9843TE0D0Q8Cr3R4JPeD7LqCyE1QQznUx0gRgJNE2f3qzXjvIs8szpSf3LxAO7r5bulLza09fDTpxK0VYApp2tI6WKI0+kXeQ0pj2Svf/Js3dewdtB7M2mGjrr7XZIgNwrCowwbR6Koqwqfqz1hq1wInedltXFeN+MU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712712304; c=relaxed/simple; bh=Gx9bCHrk1d77GFAb42nNEx6SxHXDuHF529fcfh61eHU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=tf447yklh/FUDBXTXPlIVPmd+ue0U2z6/m1AmuPySL7kQ3ftNH2fWHHXlMAzeUcvbDe6FFf6cziFKGjaVy559knSI358AKEkINTI98AudC11+ZC9a16WYC4HIE+EggJdoY89kwgWcrnuxa03aRKG1eSZR8Tz1xU+H65k8WZp6lk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DTfyx2fr; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DTfyx2fr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5FEF1C433C7; Wed, 10 Apr 2024 01:25:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1712712303; bh=Gx9bCHrk1d77GFAb42nNEx6SxHXDuHF529fcfh61eHU=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=DTfyx2frpgj15Wx6eJlg+u5fV/fmpIM4AfEo+DxtWGjhn/Cmt1p05Z5d7JEmvob4u xySbZvEzzSJxd2r7RSDkZqr/UyK9ATc6nZZYTN08boj7i1DyMEyyNCOg2ggc31R4OX sUPivJD17j0XyliKhbyXB4tV6gLcHogm1pEBhgKo1TbDIYEuoa/IXlbWRDn2SWCB5X HobqGPjiUHixyzPY2GFVCh45yHOcnhOCnoZDXL7srypRZIpu7Yw6yCZuEMHatB+6ra 1f2HT2dlRBInnMRkCLnAYLhZWM+UAp6vfx4ML+KmQSj6Zm4UMdUapyzmeUQJZ9n5SD Le5G4IC2HgEBA== Message-ID: <33644d72-e32f-40bf-9d81-b915b509bde9@kernel.org> Date: Wed, 10 Apr 2024 09:24:59 +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 Subject: Re: [f2fs-dev] [PATCH] f2fs: don't set RO when shutting down f2fs To: Jaegeuk Kim Cc: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, =?UTF-8?B?TGlnaHQgSHNpZWggKOisneaYjueHiCk=?= References: <20240404195254.556896-1-jaegeuk@kernel.org> <2c195fee-c71c-4e44-b24f-9880b3c1b6c4@kernel.org> Content-Language: en-US From: Chao Yu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 2024/4/10 0:21, Jaegeuk Kim wrote: > On 04/09, Chao Yu wrote: >> On 2024/4/5 3:52, Jaegeuk Kim wrote: >>> Shutdown does not check the error of thaw_super due to readonly, which >>> causes a deadlock like below. >>> >>> f2fs_ioc_shutdown(F2FS_GOING_DOWN_FULLSYNC) issue_discard_thread >>> - bdev_freeze >>> - freeze_super >>> - f2fs_stop_checkpoint() >>> - f2fs_handle_critical_error - sb_start_write >>> - set RO - waiting >>> - bdev_thaw >>> - thaw_super_locked >>> - return -EINVAL, if sb_rdonly() >>> - f2fs_stop_discard_thread >>> -> wait for kthread_stop(discard_thread); >>> >>> Reported-by: "Light Hsieh (謝明燈)" >>> Signed-off-by: Jaegeuk Kim >>> --- >>> fs/f2fs/super.c | 11 +++++++++-- >>> 1 file changed, 9 insertions(+), 2 deletions(-) >>> >>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c >>> index df9765b41dac..ba6288e870c5 100644 >>> --- a/fs/f2fs/super.c >>> +++ b/fs/f2fs/super.c >>> @@ -4135,9 +4135,16 @@ void f2fs_handle_critical_error(struct f2fs_sb_info *sbi, unsigned char reason, >>> if (shutdown) >>> set_sbi_flag(sbi, SBI_IS_SHUTDOWN); >>> - /* continue filesystem operators if errors=continue */ >>> - if (continue_fs || f2fs_readonly(sb)) >>> + /* >>> + * Continue filesystem operators if errors=continue. Should not set >>> + * RO by shutdown, since RO bypasses thaw_super which can hang the >>> + * system. >>> + */ >>> + if (continue_fs || f2fs_readonly(sb) || >>> + reason == STOP_CP_REASON_SHUTDOWN) { >>> + f2fs_warn(sbi, "Stopped filesystem due to readon: %d", reason); >>> return; >> >> Do we need to set RO after bdev_thaw() in f2fs_do_shutdown()? > > IIRC, shutdown doesn't need to set RO as we stopped the checkpoint. > I'm more concerned on any side effect caused by this RO change. Okay, I just wonder whether we need to follow semantics of errors=remount-ro semantics, but it looks fine since shutdown operation simulated by ioctl could not be treated as an inner critical error, errors=%s Specify f2fs behavior on critical errors. This supports modes: "panic", "continue" and "remount-ro", respectively, trigger panic immediately, continue without doing anything, and remount the partition in read-only mode. By default it uses "continue" mode. Also, it keeps the behavior consistent w/ what we do for errors=panic case. if (F2FS_OPTION(sbi).errors == MOUNT_ERRORS_PANIC && !shutdown && !system_going_down() && ^^^^^^^^^ !is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN)) panic("F2FS-fs (device %s): panic forced after error\n", sb->s_id); Thanks, > >> >> Thanks, >> >>> + } >>> f2fs_warn(sbi, "Remounting filesystem read-only"); >>> /*