From patchwork Thu Jun 2 13:45:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guoqing Jiang X-Patchwork-Id: 12867876 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 D0736C43334 for ; Thu, 2 Jun 2022 13:45:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235524AbiFBNpZ (ORCPT ); Thu, 2 Jun 2022 09:45:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235527AbiFBNpX (ORCPT ); Thu, 2 Jun 2022 09:45:23 -0400 Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2A9362997BE for ; Thu, 2 Jun 2022 06:45:21 -0700 (PDT) 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=1654177518; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=/5tYrl+aa+2cb1C5++JzzqszjuE8NbJf1R8MKi7i1hg=; b=rmyflNRgzj/tHUJ4GjoTpS+SnV9wCrSgUaKoaegiEFheDY79VZtypoGSZRDIIXV247Yx/+ KlCU/NA+SWxf8TJAfLOm5FEThJ/I2IzF2c8AtFtnE5PBgEex+dwyJo9RaLTZ2JbzzQYNs9 2Y9psS3cdZ+MkmbAX+vYePwQmYs8fd4= From: Guoqing Jiang To: song@kernel.org Cc: linux-raid@vger.kernel.org, buczek@molgen.mpg.de, logang@deltatee.com Subject: [PATCH] md: only unlock mddev from action_store Date: Thu, 2 Jun 2022 21:45:09 +0800 Message-Id: <20220602134509.16662-1-guoqing.jiang@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org The 07reshape5intr test is broke because of below path. md_reap_sync_thread -> mddev_unlock -> md_unregister_thread(&mddev->sync_thread) And md_check_recovery is triggered by, mddev_unlock -> md_wakeup_thread(mddev->thread) then mddev->reshape_position is set to MaxSector in raid5_finish_reshape since MD_RECOVERY_INTR is cleared in md_check_recovery, which means feature_map is not set with MD_FEATURE_RESHAPE_ACTIVE and superblock's reshape_position can't be updated accordingly. Since the bug which commit 8b48ec23cc51a ("md: don't unregister sync_thread with reconfig_mutex held") fixed is related with action_store path, other callers which reap sync_thread didn't need to be changed, let's 1. only unlock mddev in md_reap_sync_thread if caller is action_store, so the parameter is renamed to reflect the change. 2. save some contexts (MD_RECOVERY_INTR and reshape_position) since they could be changed by other processes, then restore them after get lock again. Fixes: 8b48ec23cc51a ("md: don't unregister sync_thread with reconfig_mutex held") Reported-by: Logan Gunthorpe Signed-off-by: Guoqing Jiang --- I suppose the previous bug still can be fixed with the change, but it is better to verify it. Donald, could you help to test the new code? Thanks, Guoqing drivers/md/md.c | 24 ++++++++++++++++++------ drivers/md/md.h | 2 +- 2 files changed, 19 insertions(+), 7 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 5c8efef13881..3387260dd55b 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -6197,7 +6197,7 @@ static void __md_stop_writes(struct mddev *mddev) flush_workqueue(md_misc_wq); if (mddev->sync_thread) { set_bit(MD_RECOVERY_INTR, &mddev->recovery); - md_reap_sync_thread(mddev, true); + md_reap_sync_thread(mddev, false); } del_timer_sync(&mddev->safemode_timer); @@ -9303,7 +9303,7 @@ void md_check_recovery(struct mddev *mddev) * ->spare_active and clear saved_raid_disk */ set_bit(MD_RECOVERY_INTR, &mddev->recovery); - md_reap_sync_thread(mddev, true); + md_reap_sync_thread(mddev, false); clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery); clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery); clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags); @@ -9338,7 +9338,7 @@ void md_check_recovery(struct mddev *mddev) goto unlock; } if (mddev->sync_thread) { - md_reap_sync_thread(mddev, true); + md_reap_sync_thread(mddev, false); goto unlock; } /* Set RUNNING before clearing NEEDED to avoid @@ -9411,18 +9411,30 @@ void md_check_recovery(struct mddev *mddev) } EXPORT_SYMBOL(md_check_recovery); -void md_reap_sync_thread(struct mddev *mddev, bool reconfig_mutex_held) +void md_reap_sync_thread(struct mddev *mddev, bool unlock_mddev) { struct md_rdev *rdev; sector_t old_dev_sectors = mddev->dev_sectors; + sector_t old_reshape_position; bool is_reshaped = false; + bool is_interrupted = false; - if (reconfig_mutex_held) + if (unlock_mddev) { + old_reshape_position = mddev->reshape_position; + if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) + is_interrupted = true; mddev_unlock(mddev); + } /* resync has finished, collect result */ md_unregister_thread(&mddev->sync_thread); - if (reconfig_mutex_held) + if (unlock_mddev) { mddev_lock_nointr(mddev); + /* restore the previous flag and position */ + mddev->reshape_position = old_reshape_position; + if (is_interrupted) + set_bit(MD_RECOVERY_INTR, &mddev->recovery); + } + if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && mddev->degraded != mddev->raid_disks) { diff --git a/drivers/md/md.h b/drivers/md/md.h index 82465a4b1588..3e3ff3b20e81 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -719,7 +719,7 @@ extern struct md_thread *md_register_thread( extern void md_unregister_thread(struct md_thread **threadp); extern void md_wakeup_thread(struct md_thread *thread); extern void md_check_recovery(struct mddev *mddev); -extern void md_reap_sync_thread(struct mddev *mddev, bool reconfig_mutex_held); +extern void md_reap_sync_thread(struct mddev *mddev, bool unlock_mddev); extern int mddev_init_writes_pending(struct mddev *mddev); extern bool md_write_start(struct mddev *mddev, struct bio *bi); extern void md_write_inc(struct mddev *mddev, struct bio *bi);