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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D59BC433F5 for ; Sat, 12 Feb 2022 01:47:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229721AbiBLBru (ORCPT ); Fri, 11 Feb 2022 20:47:50 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:42812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229447AbiBLBru (ORCPT ); Fri, 11 Feb 2022 20:47:50 -0500 Received: from out1.migadu.com (out1.migadu.com [IPv6:2001:41d0:2:863f::]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3CDD0D4 for ; Fri, 11 Feb 2022 17:47:47 -0800 (PST) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1644630462; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=zv2Vv8IiuFzJRe8OOAOV5687QRmNAPMPwTBhFBsH9XE=; b=rqx4m7Hif5ok/u83JuWB/8Qx+cSU8qcOaFGReA7cCCyisfpo5BMxLobkeFIO2eTMZhysGM E41sNLXyL/q8Ip7qPnDoEVFkbQ9HrjdRv5TMeXn1qkGNOOyFMgMzL0lvxQDFFslf5kaXOw FsEzKKxunm4fB5ZeXRTMUWElFPDEwks= From: Guoqing Jiang Subject: Re: [PATCH 3/3] raid5: introduce MD_BROKEN To: Mariusz Tkaczyk , song@kernel.org Cc: linux-raid@vger.kernel.org References: <20220127153912.26856-1-mariusz.tkaczyk@linux.intel.com> <20220127153912.26856-4-mariusz.tkaczyk@linux.intel.com> Message-ID: Date: Sat, 12 Feb 2022 09:47:38 +0800 MIME-Version: 1.0 In-Reply-To: <20220127153912.26856-4-mariusz.tkaczyk@linux.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org On 1/27/22 11:39 PM, Mariusz Tkaczyk wrote: > Raid456 module had allowed to achieve failed state. It was fixed by > fb73b357fb9 ("raid5: block failing device if raid will be failed"). > This fix introduces a bug, now if raid5 fails during IO, it may result > with a hung task without completion. Faulty flag on the device is > necessary to process all requests and is checked many times, mainly in > analyze_stripe(). > Allow to set faulty on drive again and set MD_BROKEN if raid is failed. > > As a result, this level is allowed to achieve failed state again, but > communication with userspace (via -EBUSY status) will be preserved. > > This restores possibility to fail array via #mdadm --set-faulty command > and will be fixed by additional verification on mdadm side. Again, you better to send mdadm change along with the series. > Reproduction steps: > mdadm -CR imsm -e imsm -n 3 /dev/nvme[0-2]n1 > mdadm -CR r5 -e imsm -l5 -n3 /dev/nvme[0-2]n1 --assume-clean > mkfs.xfs /dev/md126 -f > mount /dev/md126 /mnt/root/ > > fio --filename=/mnt/root/file --size=5GB --direct=1 --rw=randrw > --bs=64k --ioengine=libaio --iodepth=64 --runtime=240 --numjobs=4 > --time_based --group_reporting --name=throughput-test-job > --eta-newline=1 & > > echo 1 > /sys/block/nvme2n1/device/device/remove > echo 1 > /sys/block/nvme1n1/device/device/remove > > [ 1475.787779] Call Trace: > [ 1475.793111] __schedule+0x2a6/0x700 > [ 1475.799460] schedule+0x38/0xa0 > [ 1475.805454] raid5_get_active_stripe+0x469/0x5f0 [raid456] > [ 1475.813856] ? finish_wait+0x80/0x80 > [ 1475.820332] raid5_make_request+0x180/0xb40 [raid456] > [ 1475.828281] ? finish_wait+0x80/0x80 > [ 1475.834727] ? finish_wait+0x80/0x80 > [ 1475.841127] ? finish_wait+0x80/0x80 > [ 1475.847480] md_handle_request+0x119/0x190 > [ 1475.854390] md_make_request+0x8a/0x190 > [ 1475.861041] generic_make_request+0xcf/0x310 > [ 1475.868145] submit_bio+0x3c/0x160 > [ 1475.874355] iomap_dio_submit_bio.isra.20+0x51/0x60 > [ 1475.882070] iomap_dio_bio_actor+0x175/0x390 > [ 1475.889149] iomap_apply+0xff/0x310 > [ 1475.895447] ? iomap_dio_bio_actor+0x390/0x390 > [ 1475.902736] ? iomap_dio_bio_actor+0x390/0x390 > [ 1475.909974] iomap_dio_rw+0x2f2/0x490 > [ 1475.916415] ? iomap_dio_bio_actor+0x390/0x390 > [ 1475.923680] ? atime_needs_update+0x77/0xe0 > [ 1475.930674] ? xfs_file_dio_aio_read+0x6b/0xe0 [xfs] > [ 1475.938455] xfs_file_dio_aio_read+0x6b/0xe0 [xfs] > [ 1475.946084] xfs_file_read_iter+0xba/0xd0 [xfs] > [ 1475.953403] aio_read+0xd5/0x180 > [ 1475.959395] ? _cond_resched+0x15/0x30 > [ 1475.965907] io_submit_one+0x20b/0x3c0 > [ 1475.972398] __x64_sys_io_submit+0xa2/0x180 > [ 1475.979335] ? do_io_getevents+0x7c/0xc0 > [ 1475.986009] do_syscall_64+0x5b/0x1a0 > [ 1475.992419] entry_SYSCALL_64_after_hwframe+0x65/0xca > [ 1476.000255] RIP: 0033:0x7f11fc27978d > [ 1476.006631] Code: Bad RIP value. > [ 1476.073251] INFO: task fio:3877 blocked for more than 120 seconds. Does it also happen to non imsm array? And did you try to reproduce it with revert fb73b357fb? I suppose fb73b357fb9 introduced the regression given it is fixed by this one. > Fixes: fb73b357fb9 ("raid5: block failing device if raid will be failed") > Signed-off-by: Mariusz Tkaczyk > --- > drivers/md/raid1.c | 1 + > drivers/md/raid5.c | 49 +++++++++++++++++++++++----------------------- > 2 files changed, 25 insertions(+), 25 deletions(-) > > diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c > index b222bafa1196..58c8eddb0f55 100644 > --- a/drivers/md/raid1.c > +++ b/drivers/md/raid1.c > @@ -1627,6 +1627,7 @@ static void raid1_status(struct seq_file *seq, struct mddev *mddev) > * - if is on @rdev is removed. > * - if is off, @rdev is not removed, but recovery from it is disabled (@rdev is > * very likely to fail). > + * You probably don't want to touch raid1 file in this patch. > * In both cases, &MD_BROKEN will be set in &mddev->flags. > */ > static void raid1_error(struct mddev *mddev, struct md_rdev *rdev) > diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c > index 1240a5c16af8..bee953c8007f 100644 > --- a/drivers/md/raid5.c > +++ b/drivers/md/raid5.c > @@ -686,17 +686,21 @@ int raid5_calc_degraded(struct r5conf *conf) > return degraded; > } > > -static int has_failed(struct r5conf *conf) > +static bool has_failed(struct r5conf *conf) > { > - int degraded; > + int degraded = conf->mddev->degraded; > > - if (conf->mddev->reshape_position == MaxSector) > - return conf->mddev->degraded > conf->max_degraded; > + if (test_bit(MD_BROKEN, &conf->mddev->flags)) > + return true; If one member disk was set Faulty which caused BROKEN was set, is it possible to re-add the same member disk again? [root@vm ~]# echo faulty > /sys/block/md0/md/dev-loop1/state [root@vm ~]# cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] md0 : active raid5 loop2[2] loop1[0](F)       1046528 blocks super 1.2 level 5, 512k chunk, algorithm 2 [2/1] [_U]       bitmap: 0/1 pages [0KB], 65536KB chunk unused devices: [root@vm ~]# echo re-add > /sys/block/md0/md/dev-loop1/state [root@vm ~]# cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] md0 : active raid5 loop2[2] loop1[0]       1046528 blocks super 1.2 level 5, 512k chunk, algorithm 2 [2/2] [UU]       bitmap: 0/1 pages [0KB], 65536KB chunk unused devices: And have you run mdadm test against the series? > - degraded = raid5_calc_degraded(conf); > - if (degraded > conf->max_degraded) > - return 1; > - return 0; > + if (conf->mddev->reshape_position != MaxSector) > + degraded = raid5_calc_degraded(conf); > + > + if (degraded > conf->max_degraded) { > + set_bit(MD_BROKEN, &conf->mddev->flags); Why not set BROKEN flags in err handler to align with other levels? Or do it in md_error only. > + return true; > + } > + return false; > } > > struct stripe_head * > @@ -2877,34 +2881,29 @@ static void raid5_error(struct mddev *mddev, struct md_rdev *rdev) > unsigned long flags; > pr_debug("raid456: error called\n"); > > + pr_crit("md/raid:%s: Disk failure on %s, disabling device.\n", > + mdname(mddev), bdevname(rdev->bdev, b)); > + > spin_lock_irqsave(&conf->device_lock, flags); > + set_bit(Faulty, &rdev->flags); > + clear_bit(In_sync, &rdev->flags); > + mddev->degraded = raid5_calc_degraded(conf); > > - if (test_bit(In_sync, &rdev->flags) && > - mddev->degraded == conf->max_degraded) { > - /* > - * Don't allow to achieve failed state > - * Don't try to recover this device > - */ > + if (has_failed(conf)) { > conf->recovery_disabled = mddev->recovery_disabled; > - spin_unlock_irqrestore(&conf->device_lock, flags); > - return; Ok, I think commit fb73b357fb985cc652a72a41541d25915c7f9635 is effectively reverted by this hunk. So I would prefer to separate the revert part from this patch, just my 0.02$. Thanks, Guoqing