Messages in this thread Patch in this message | | | From | Aleksa Sarai <> | Subject | [PATCH] btrfs: resume qgroup rescan on rw remount | Date | Tue, 4 Jul 2017 21:49:06 +1000 |
| |
Several distributions mount the "proper root" as ro during initrd and then remount it as rw before pivot_root(2). Thus, if a rescan had been aborted by a previous shutdown, the rescan would never be resumed.
This issue would manifest itself as several btrfs ioctl(2)s causing the entire machine to hang when btrfs_qgroup_wait_for_completion was hit (due to the fs_info->qgroup_rescan_running flag being set but the rescan itself not being resumed). Notably, Docker's btrfs storage driver makes regular use of BTRFS_QUOTA_CTL_DISABLE and BTRFS_IOC_QUOTA_RESCAN_WAIT (causing this problem to be manifested on boot for some machines).
Cc: <stable@vger.kernel.org> # v3.11+ Cc: Jeff Mahoney <jeffm@suse.com> Fixes: b382a324b60f ("Btrfs: fix qgroup rescan resume on mount") Signed-off-by: Aleksa Sarai <asarai@suse.de> --- fs/btrfs/super.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 6346876c97ea..ff6690389343 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1821,6 +1821,8 @@ static int btrfs_remount(struct super_block *sb, int *flags, char *data) goto restore; } + btrfs_qgroup_rescan_resume(fs_info); + if (!fs_info->uuid_root) { btrfs_info(fs_info, "creating UUID tree"); ret = btrfs_create_uuid_tree(fs_info); -- 2.13.2
| |