diff mbox series

block: clear GD_NEED_PART_SCAN later in bdev_disk_changed

Message ID 20210323085219.24428-1-chris.chiu@canonical.com (mailing list archive)
State New, archived
Headers show
Series block: clear GD_NEED_PART_SCAN later in bdev_disk_changed | expand

Commit Message

Chris Chiu March 23, 2021, 8:52 a.m. UTC 
From: Chris Chiu <chris.chiu@canonical.com>

The GD_NEED_PART_SCAN is set by bdev_check_media_change to initiate
a partition scan while removing a block device. It should be cleared
after blk_drop_paritions because blk_drop_paritions could return
-EBUSY and then the consequence __blkdev_get has no chance to do
delete_partition if GD_NEED_PART_SCAN already cleared.

It causes some problems on some card readers. Ex. Realtek card
reader 0bda:0328 and 0bda:0158. The device node of the partition
will not disappear after the memory card removed. Thus the user
applications can not update the device mapping correctly.

BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1920874
Signed-off-by: Chris Chiu <chris.chiu@canonical.com>
---
 fs/block_dev.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Christoph Hellwig March 23, 2021, 3:51 p.m. UTC | #1 
Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>
Jens Axboe March 23, 2021, 3:58 p.m. UTC | #2 
On 3/23/21 2:52 AM, chris.chiu@canonical.com wrote:
> From: Chris Chiu <chris.chiu@canonical.com>
> 
> The GD_NEED_PART_SCAN is set by bdev_check_media_change to initiate
> a partition scan while removing a block device. It should be cleared
> after blk_drop_paritions because blk_drop_paritions could return
> -EBUSY and then the consequence __blkdev_get has no chance to do
> delete_partition if GD_NEED_PART_SCAN already cleared.
> 
> It causes some problems on some card readers. Ex. Realtek card
> reader 0bda:0328 and 0bda:0158. The device node of the partition
> will not disappear after the memory card removed. Thus the user
> applications can not update the device mapping correctly.

Applied, thanks.
diff mbox series

Patch

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 92ed7d5df677..28d583fcdc2c 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1240,13 +1240,13 @@  int bdev_disk_changed(struct block_device *bdev, bool invalidate)
 
 	lockdep_assert_held(&bdev->bd_mutex);
 
-	clear_bit(GD_NEED_PART_SCAN, &bdev->bd_disk->state);
-
 rescan:
 	ret = blk_drop_partitions(bdev);
 	if (ret)
 		return ret;
 
+	clear_bit(GD_NEED_PART_SCAN, &disk->state);
+
 	/*
 	 * Historically we only set the capacity to zero for devices that
 	 * support partitions (independ of actually having partitions created).