From: Anand Jain <anand.jain@xxxxxxxxxx> Commit b7cb29e666fe79dda5dbe5f57fb7c92413bf161c upstream. When we add a device to the seed filesystem (sprouting) it is a new filesystem (and fsid) on the device added. Update the latest_dev so that /proc/self/mounts shows the correct device. Example: $ btrfstune -S1 /dev/vg/seed $ mount /dev/vg/seed /btrfs mount: /btrfs: WARNING: device write-protected, mounted read-only. $ cat /proc/self/mounts | grep btrfs /dev/mapper/vg-seed /btrfs btrfs ro,relatime,space_cache,subvolid=5,subvol=/ 0 0 $ btrfs dev add -f /dev/vg/new /btrfs Before: $ cat /proc/self/mounts | grep btrfs /dev/mapper/vg-seed /btrfs btrfs ro,relatime,space_cache,subvolid=5,subvol=/ 0 0 After: $ cat /proc/self/mounts | grep btrfs /dev/mapper/vg-new /btrfs btrfs ro,relatime,space_cache,subvolid=5,subvol=/ 0 0 Tested-by: Su Yue <l@xxxxxxxxxx> Signed-off-by: Anand Jain <anand.jain@xxxxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Anand Jain <anand.jain@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/btrfs/volumes.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2634,6 +2634,8 @@ int btrfs_init_new_device(struct btrfs_f btrfs_abort_transaction(trans, ret); goto error_trans; } + btrfs_assign_next_active_device(fs_info->fs_devices->latest_dev, + device); } device->fs_devices = fs_devices;