From patchwork Thu Feb 1 09:25:46 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 13540832 Received: from dggsgout11.his.huawei.com (unknown [45.249.212.51]) (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 5F64515AAAA for ; Thu, 1 Feb 2024 09:30:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706779831; cv=none; b=guonD9HoegDK4ZkhheMeVS3yLbKGowm6d1kujdYbyyRCP9qhpWOnwDU4cPXBaQRtpBB1fZzZoPJLW+ImGMiJBAbTP9MJqyitWnrI3izB1mg7myzkdg9pGgByp5tynnOhBmVTvSAOlDmb9PofiJUVw0Y40KkIiU2F1oQJe62YMtU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706779831; c=relaxed/simple; bh=niaIFrprWvPwC2Lv0RN5Cl1tFCytXopzeriQpGSoAMg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=b4mpg9q1FujBK6Nz2161MO/M3lcCM0kKEG+jq56xf0aydjnCy0hlSghYACdEqP5cgyegN2giEuhVgK2NAq0yEj62MWJ1y7oH49KGjPS6Jgf0dEu6sTi9ynFERSxrQxP3r7Y/ZjYcixkGSrKDltyQ7x0uM0gwyg9K6QMqVPhtWJs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.93.142]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4TQYXt6fn6z4f3kjd for ; Thu, 1 Feb 2024 17:30:22 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.112]) by mail.maildlp.com (Postfix) with ESMTP id 835451A0172 for ; Thu, 1 Feb 2024 17:30:25 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP1 (Coremail) with SMTP id cCh0CgCXaBGtZLtl8V6KCg--.33515S5; Thu, 01 Feb 2024 17:30:25 +0800 (CST) From: Yu Kuai To: mpatocka@redhat.com, heinzm@redhat.com, xni@redhat.com, blazej.kucman@linux.intel.com, agk@redhat.com, snitzer@kernel.org, dm-devel@lists.linux.dev, song@kernel.org, yukuai3@huawei.com, jbrassow@f14.redhat.com, neilb@suse.de, shli@fb.com, akpm@osdl.org Cc: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com Subject: [PATCH v5 01/14] md: don't ignore suspended array in md_check_recovery() Date: Thu, 1 Feb 2024 17:25:46 +0800 Message-Id: <20240201092559.910982-2-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240201092559.910982-1-yukuai1@huaweicloud.com> References: <20240201092559.910982-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: dm-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: cCh0CgCXaBGtZLtl8V6KCg--.33515S5 X-Coremail-Antispam: 1UD129KBjvJXoWxJryDAF43ArW7JrWrZr1xGrg_yoW8ZFy7pa yIkF1YyrWjyFZ7Aa4qka4UZa4rAr1jqrW5AFy3u34rCa4fKw43CrWYgFyDXFyqkFyxKrZY vw4rJa15uw18KF7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBE14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jr4l82xGYIkIc2 x26xkF7I0E14v26r4j6ryUM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJw A2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAS 0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2 IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0 Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kIc2 xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v2 6r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2 Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_ Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMI IF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JU4T5dUUUUU = X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ From: Yu Kuai mddev_suspend() never stop sync_thread, hence it doesn't make sense to ignore suspended array in md_check_recovery(), which might cause sync_thread can't be unregistered. After commit f52f5c71f3d4 ("md: fix stopping sync thread"), following hang can be triggered by test shell/integrity-caching.sh: 1) suspend the array: raid_postsuspend mddev_suspend 2) stop the array: raid_dtr md_stop __md_stop_writes stop_sync_thread set_bit(MD_RECOVERY_INTR, &mddev->recovery); md_wakeup_thread_directly(mddev->sync_thread); wait_event(..., !test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) 3) sync thread done: md_do_sync set_bit(MD_RECOVERY_DONE, &mddev->recovery); md_wakeup_thread(mddev->thread); 4) daemon thread can't unregister sync thread: md_check_recovery if (mddev->suspended) return; -> return directly md_read_sync_thread clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery); -> MD_RECOVERY_RUNNING can't be cleared, hence step 2 hang; This problem is not just related to dm-raid, fix it by ignoring suspended array in md_check_recovery(). And follow up patches will improve dm-raid better to frozen sync thread during suspend. Reported-by: Mikulas Patocka Closes: https://lore.kernel.org/all/8fb335e-6d2c-dbb5-d7-ded8db5145a@redhat.com/ Fixes: 68866e425be2 ("MD: no sync IO while suspended") Fixes: f52f5c71f3d4 ("md: fix stopping sync thread") Signed-off-by: Yu Kuai --- drivers/md/md.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 2266358d8074..07b80278eaa5 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -9469,9 +9469,6 @@ static void md_start_sync(struct work_struct *ws) */ void md_check_recovery(struct mddev *mddev) { - if (READ_ONCE(mddev->suspended)) - return; - if (mddev->bitmap) md_bitmap_daemon_work(mddev);