block: Fix race during disk initialization
authorSigned-off-by: Jan Kara <jack@suse.cz>
Thu, 16 Sep 2010 18:36:36 +0000 (20:36 +0200)
committerJens Axboe <jaxboe@fusionio.com>
Thu, 16 Sep 2010 18:36:36 +0000 (20:36 +0200)
commit01ea50638bc04ca5259f5711fcdedefcdde1cf43
treec525dc13b05feab90d71b78a1d7adb0ddde081ea
parent2786c4e5e54802c34297e55050fef3e862a27b3f
block: Fix race during disk initialization

When a new disk is being discovered, add_disk() first ties the bdev to gendisk
(via register_disk()->blkdev_get()) and only after that calls
bdi_register_bdev(). Because register_disk() also creates disk's kobject, it
can happen that userspace manages to open and modify the device's data (or
inode) before its BDI is properly initialized leading to a warning in
__mark_inode_dirty().

Fix the problem by registering BDI early enough.

This patch addresses https://bugzilla.kernel.org/show_bug.cgi?id=16312

Cc: stable@kernel.org
Reported-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
block/genhd.c