Commit 760515d2 authored by Anand Jain's avatar Anand Jain Committed by Yifan Qiao
Browse files

btrfs: remove stale comment about the btrfs_show_devname 

mainline inclusion
from mainline-v5.16-rc1
commit cdccc03a
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IA77UW
CVE: CVE-2021-47599

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cdccc03a8a369b59cff5e7ea3292511cfa551120



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

There were few lockdep warnings because btrfs_show_devname() was using
device_list_mutex as recorded in the commits:

  0ccd0528 ("btrfs: fix a possible umount deadlock")
  779bf3fe ("btrfs: fix lock dep warning, move scratch dev out of device_list_mutex and uuid_mutex")

And finally, commit 88c14590 ("btrfs: use RCU in btrfs_show_devname
for device list traversal") removed the device_list_mutex from
btrfs_show_devname for performance reasons.

This patch removes a stale comment about the function
btrfs_show_devname and device_list_mutex.

Signed-off-by: default avatarAnand Jain <anand.jain@oracle.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarYifan Qiao <qiaoyifan4@huawei.com>
parent 1663e93c

fs/btrfs/volumes.c

+0 −7
Original line number Diff line number Diff line
@@ -2317,13 +2317,6 @@ void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev) 


	mutex_unlock(&fs_devices->device_list_mutex);



	/*

	 * The update_dev_time() with in btrfs_scratch_superblocks()

	 * may lead to a call to btrfs_show_devname() which will try

	 * to hold device_list_mutex. And here this device

	 * is already out of device list, so we don't have to hold

	 * the device_list_mutex lock.

	 */

	btrfs_scratch_superblocks(tgtdev->fs_info, tgtdev->bdev,

				  tgtdev->name->str);