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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 47F21C04E53 for ; Wed, 15 May 2019 11:59:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1A7D520657 for ; Wed, 15 May 2019 11:59:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557921560; bh=BKhx40uVIX9ZfO8KlvUI+e+N1GOP53trJlrGdphMynE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=dzjj/ZNJqY8mYr1dp98Q6G3xWmx1Qle3kRLQYVH1wtPIZZXUy5LMo66v0/GKbIIaE 5Brm94GlT70EHj4IBYHRp3bxrqlc5nlRBwZzGrzvw1lL0iCq8PXW8UZ19m0mYc7CnQ 9ewMCKtjqUPwJRO7++USC+8pVAROk3oSQiiQdLv4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730315AbfEOLPj (ORCPT ); Wed, 15 May 2019 07:15:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:52160 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730324AbfEOLPh (ORCPT ); Wed, 15 May 2019 07:15:37 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6750C2084F; Wed, 15 May 2019 11:15:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557918935; bh=BKhx40uVIX9ZfO8KlvUI+e+N1GOP53trJlrGdphMynE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zDRE5SymLzwAJgatGg6qQrci5CzjfsUT3w1PgdKVOuzQ9SoUThNtIuYAgziDzD24M wMkrHj0+fvjGvMddbfxQqM1i7YcmokKNd+ebb033jTeMtGWrO7Fvzxw+R6TjaecqBl 2Im911lh+u1kMmHfA5rLZ0IjYMCTOr/UmVG8HnaA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiao Ni , David Jeffery , Nigel Croxon , Song Liu , Jens Axboe Subject: [PATCH 4.9 33/51] Dont jump to compute_result state from check_result state Date: Wed, 15 May 2019 12:56:08 +0200 Message-Id: <20190515090626.261933700@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190515090616.669619870@linuxfoundation.org> References: <20190515090616.669619870@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Nigel Croxon commit 4f4fd7c5798bbdd5a03a60f6269cf1177fbd11ef upstream. Changing state from check_state_check_result to check_state_compute_result not only is unsafe but also doesn't appear to serve a valid purpose. A raid6 check should only be pushing out extra writes if doing repair and a mis-match occurs. The stripe dev management will already try and do repair writes for failing sectors. This patch makes the raid6 check_state_check_result handling work more like raid5's. If somehow too many failures for a check, just quit the check operation for the stripe. When any checks pass, don't try and use check_state_compute_result for a purpose it isn't needed for and is unsafe for. Just mark the stripe as in sync for passing its parity checks and let the stripe dev read/write code and the bad blocks list do their job handling I/O errors. Repro steps from Xiao: These are the steps to reproduce this problem: 1. redefined OPT_MEDIUM_ERR_ADDR to 12000 in scsi_debug.c 2. insmod scsi_debug.ko dev_size_mb=11000 max_luns=1 num_tgts=1 3. mdadm --create /dev/md127 --level=6 --raid-devices=5 /dev/sde1 /dev/sde2 /dev/sde3 /dev/sde5 /dev/sde6 sde is the disk created by scsi_debug 4. echo "2" >/sys/module/scsi_debug/parameters/opts 5. raid-check It panic: [ 4854.730899] md: data-check of RAID array md127 [ 4854.857455] sd 5:0:0:0: [sdr] tag#80 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 4854.859246] sd 5:0:0:0: [sdr] tag#80 Sense Key : Medium Error [current] [ 4854.860694] sd 5:0:0:0: [sdr] tag#80 Add. Sense: Unrecovered read error [ 4854.862207] sd 5:0:0:0: [sdr] tag#80 CDB: Read(10) 28 00 00 00 2d 88 00 04 00 00 [ 4854.864196] print_req_error: critical medium error, dev sdr, sector 11656 flags 0 [ 4854.867409] sd 5:0:0:0: [sdr] tag#100 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 4854.869469] sd 5:0:0:0: [sdr] tag#100 Sense Key : Medium Error [current] [ 4854.871206] sd 5:0:0:0: [sdr] tag#100 Add. Sense: Unrecovered read error [ 4854.872858] sd 5:0:0:0: [sdr] tag#100 CDB: Read(10) 28 00 00 00 2e e0 00 00 08 00 [ 4854.874587] print_req_error: critical medium error, dev sdr, sector 12000 flags 4000 [ 4854.876456] sd 5:0:0:0: [sdr] tag#101 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 4854.878552] sd 5:0:0:0: [sdr] tag#101 Sense Key : Medium Error [current] [ 4854.880278] sd 5:0:0:0: [sdr] tag#101 Add. Sense: Unrecovered read error [ 4854.881846] sd 5:0:0:0: [sdr] tag#101 CDB: Read(10) 28 00 00 00 2e e8 00 00 08 00 [ 4854.883691] print_req_error: critical medium error, dev sdr, sector 12008 flags 4000 [ 4854.893927] sd 5:0:0:0: [sdr] tag#166 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 4854.896002] sd 5:0:0:0: [sdr] tag#166 Sense Key : Medium Error [current] [ 4854.897561] sd 5:0:0:0: [sdr] tag#166 Add. Sense: Unrecovered read error [ 4854.899110] sd 5:0:0:0: [sdr] tag#166 CDB: Read(10) 28 00 00 00 2e e0 00 00 10 00 [ 4854.900989] print_req_error: critical medium error, dev sdr, sector 12000 flags 0 [ 4854.902757] md/raid:md127: read error NOT corrected!! (sector 9952 on sdr1). [ 4854.904375] md/raid:md127: read error NOT corrected!! (sector 9960 on sdr1). [ 4854.906201] ------------[ cut here ]------------ [ 4854.907341] kernel BUG at drivers/md/raid5.c:4190! raid5.c:4190 above is this BUG_ON: handle_parity_checks6() ... BUG_ON(s->uptodate < disks - 1); /* We don't need Q to recover */ Cc: # v3.16+ OriginalAuthor: David Jeffery Cc: Xiao Ni Tested-by: David Jeffery Signed-off-by: David Jeffy Signed-off-by: Nigel Croxon Signed-off-by: Song Liu Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid5.c | 19 ++++--------------- 1 file changed, 4 insertions(+), 15 deletions(-) --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -3914,26 +3914,15 @@ static void handle_parity_checks6(struct case check_state_check_result: sh->check_state = check_state_idle; + if (s->failed > 1) + break; /* handle a successful check operation, if parity is correct * we are done. Otherwise update the mismatch count and repair * parity if !MD_RECOVERY_CHECK */ if (sh->ops.zero_sum_result == 0) { - /* both parities are correct */ - if (!s->failed) - set_bit(STRIPE_INSYNC, &sh->state); - else { - /* in contrast to the raid5 case we can validate - * parity, but still have a failure to write - * back - */ - sh->check_state = check_state_compute_result; - /* Returning at this point means that we may go - * off and bring p and/or q uptodate again so - * we make sure to check zero_sum_result again - * to verify if p or q need writeback - */ - } + /* Any parity checked was correct */ + set_bit(STRIPE_INSYNC, &sh->state); } else { atomic64_add(STRIPE_SECTORS, &conf->mddev->resync_mismatches); if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery))