Commit f392c8ed authored by Yu Kuai's avatar Yu Kuai Committed by Zheng Zengkai
Browse files

block: fix regression for dm 

hulk inclusion
category: bugfix
bugzilla: 187345, https://gitee.com/openeuler/kernel/issues/I5L5ZG


CVE: NA

--------------------------------

Commit d7c2ddc8 ("block: fix that part scan is disabled in
device_add_disk()") introduce a regression:

Test procedures:
dmsetup create test --notable
dmsetup remove test

Test result:
dmsetup will stuck forever

Root cause:
before:
1) dmsetup creat
    add_disk_add_disk_no_queue_reg()
     scan partitions
     uevent
2) blk_register_queue -> notable will not call this
3) dmsetup remove
    wait for uevent

after:
1) dmsetup creat
    add_disk_add_disk_no_queue_reg()
2) blk_register_queue() -> notable will not call this
    scan_partitions
    uevent
3) dmsetup remove
    wait for uevent -> impossible for notable

Fix the problem by moving scan_partitions and uevent from
blk_register_queue() to the end of add_disk_add_disk_no_queue_reg().

Fixes: d7c2ddc8 ("block: fix that part scan is disabled in device_add_disk()")
Signed-off-by: default avatarYu Kuai <yukuai3@huawei.com>
Reviewed-by: default avatarJason Yan <yanaijie@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent c26ea58d

block/blk-sysfs.c

+0 −45
Original line number Diff line number Diff line
@@ -821,38 +821,6 @@ struct kobj_type blk_queue_ktype = { 
	.release	= blk_release_queue,

};



static void disk_scan_partitions(struct gendisk *disk)

{

	struct block_device *bdev;



	if (!get_capacity(disk) || !disk_part_scan_enabled(disk))

		return;



	set_bit(GD_NEED_PART_SCAN, &disk->state);

	bdev = blkdev_get_by_dev(disk_devt(disk), FMODE_READ, NULL);

	if (!IS_ERR(bdev))

		blkdev_put(bdev, FMODE_READ);

}



static void disk_init_partition(struct gendisk *disk)

{

	struct device *ddev = disk_to_dev(disk);

	struct disk_part_iter piter;

	struct hd_struct *part;



	disk_scan_partitions(disk);



	/* announce disk after possible partitions are created */

	dev_set_uevent_suppress(ddev, 0);

	kobject_uevent(&ddev->kobj, KOBJ_ADD);



	/* announce possible partitions */

	disk_part_iter_init(&piter, disk, 0);

	while ((part = disk_part_iter_next(&piter)))

		kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);

	disk_part_iter_exit(&piter);

}



/**

 * blk_register_queue - register a block layer queue with sysfs

 * @disk: Disk of which the request queue should be registered with sysfs.
@@ -942,22 +910,9 @@ int blk_register_queue(struct gendisk *disk) 
		kobject_uevent(&q->elevator->kobj, KOBJ_ADD);

	mutex_unlock(&q->sysfs_lock);





	/*

	 * Set the flag at last, so that block devcie can't be opened

	 * before it's registration is done.

	 */

	disk->flags |= GENHD_FL_UP;

	ret = 0;

unlock:

	mutex_unlock(&q->sysfs_dir_lock);

	/*

	 * Init partitions after releasing 'sysfs_dir_lock', otherwise lockdep

	 * will be confused because it will treat 'bd_mutex' from different

	 * devices as the same lock.

	 */

	if (!ret)

		disk_init_partition(disk);



	return ret;

}

block/genhd.c

+39 −0
Original line number Diff line number Diff line
@@ -736,6 +736,38 @@ static void register_disk(struct device *parent, struct gendisk *disk, 
	}

}



static void disk_scan_partitions(struct gendisk *disk)

{

	struct block_device *bdev;



	if (!get_capacity(disk) || !disk_part_scan_enabled(disk))

		return;



	set_bit(GD_NEED_PART_SCAN, &disk->state);

	bdev = blkdev_get_by_dev(disk_devt(disk), FMODE_READ, NULL);

	if (!IS_ERR(bdev))

		blkdev_put(bdev, FMODE_READ);

}



static void disk_init_partition(struct gendisk *disk)

{

	struct device *ddev = disk_to_dev(disk);

	struct disk_part_iter piter;

	struct hd_struct *part;



	disk_scan_partitions(disk);



	/* announce disk after possible partitions are created */

	dev_set_uevent_suppress(ddev, 0);

	kobject_uevent(&ddev->kobj, KOBJ_ADD);



	/* announce possible partitions */

	disk_part_iter_init(&piter, disk, 0);

	while ((part = disk_part_iter_next(&piter)))

		kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);

	disk_part_iter_exit(&piter);

}



/**

 * __device_add_disk - add disk information to kernel list

 * @parent: parent device for the disk
@@ -814,6 +846,13 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk, 


	disk_add_events(disk);

	blk_integrity_add(disk);



	/*

	 * Set the flag at last, so that block devcie can't be opened

	 * before it's registration is done.

	 */

	disk->flags |= GENHD_FL_UP;

	disk_init_partition(disk);

}



void device_add_disk(struct device *parent, struct gendisk *disk,