block: fix a race between del_gendisk and BLKRRPART
[ Upstream commit bc6a385132601c29a6da1dbf8148c0d3c9ad36dc ]
When BLKRRPART is called concurrently with del_gendisk, the partitions
rescan can create a stale partition that will never be be cleaned up.
Fix this by checking the the disk is up before rescanning partitions
while under bd_mutex.
Signed-off-by: Gulam Mohamed <[email protected]>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Ming Lei <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
diff --git a/fs/block_dev.c b/fs/block_dev.c
index cacea6b..29f020c 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1408,6 +1408,9 @@ int bdev_disk_changed(struct block_device *bdev, bool invalidate)
lockdep_assert_held(&bdev->bd_mutex);
+ if (!(disk->flags & GENHD_FL_UP))
+ return -ENXIO;
+
rescan:
ret = blk_drop_partitions(bdev);
if (ret)
