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 1C6662F24 for ; Wed, 12 Apr 2023 08:52:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 95935C433EF; Wed, 12 Apr 2023 08:52:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1681289540; bh=W+Vjlm2iY0I/9rDEX9/aNsvHrOsLd5xaqaAFZVmLpBA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XX5EeqfHainBgZ6g+IG1JKE0jYy2jwfUDvx/VzXINwHe82PGSI1d1eszb2MQKCSTe urzkIFhwOd1pbxzhQ9AYZ1X5esknto/m6ubLe9FLh3Z2By7PvLZWR0r9mhBKIH5rz1 gch+kNsonWW/2gliK3P13F8roKQKWK/1IuUfXBk4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jan Kara , Ming Lei , Yu Kuai , Jens Axboe , Sasha Levin Subject: [PATCH 6.2 138/173] block: dont set GD_NEED_PART_SCAN if scan partition failed Date: Wed, 12 Apr 2023 10:34:24 +0200 Message-Id: <20230412082843.689956796@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230412082838.125271466@linuxfoundation.org> References: <20230412082838.125271466@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Yu Kuai [ Upstream commit 3723091ea1884d599cc8b8bf719d6f42e8d4d8b1 ] Currently if disk_scan_partitions() failed, GD_NEED_PART_SCAN will still set, and partition scan will be proceed again when blkdev_get_by_dev() is called. However, this will cause a problem that re-assemble partitioned raid device will creat partition for underlying disk. Test procedure: mdadm -CR /dev/md0 -l 1 -n 2 /dev/sda /dev/sdb -e 1.0 sgdisk -n 0:0:+100MiB /dev/md0 blockdev --rereadpt /dev/sda blockdev --rereadpt /dev/sdb mdadm -S /dev/md0 mdadm -A /dev/md0 /dev/sda /dev/sdb Test result: underlying disk partition and raid partition can be observed at the same time Note that this can still happen in come corner cases that GD_NEED_PART_SCAN can be set for underlying disk while re-assemble raid device. Fixes: e5cfefa97bcc ("block: fix scan partition for exclusively open device again") Reviewed-by: Jan Kara Reviewed-by: Ming Lei Signed-off-by: Yu Kuai Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/genhd.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/block/genhd.c b/block/genhd.c index 9c4c9aa559ab8..7082032636035 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -368,7 +368,6 @@ int disk_scan_partitions(struct gendisk *disk, fmode_t mode) if (disk->open_partitions) return -EBUSY; - set_bit(GD_NEED_PART_SCAN, &disk->state); /* * If the device is opened exclusively by current thread already, it's * safe to scan partitons, otherwise, use bd_prepare_to_claim() to @@ -381,12 +380,19 @@ int disk_scan_partitions(struct gendisk *disk, fmode_t mode) return ret; } + set_bit(GD_NEED_PART_SCAN, &disk->state); bdev = blkdev_get_by_dev(disk_devt(disk), mode & ~FMODE_EXCL, NULL); if (IS_ERR(bdev)) ret = PTR_ERR(bdev); else blkdev_put(bdev, mode & ~FMODE_EXCL); + /* + * If blkdev_get_by_dev() failed early, GD_NEED_PART_SCAN is still set, + * and this will cause that re-assemble partitioned raid device will + * creat partition for underlying disk. + */ + clear_bit(GD_NEED_PART_SCAN, &disk->state); if (!(mode & FMODE_EXCL)) bd_abort_claiming(disk->part0, disk_scan_partitions); return ret; -- 2.39.2