解决办法：
# systemctl stop docker.service
# thin_check /var/lib/docker/devicemapper/devicemapper/metadata如果还有问题，则：
# thin_check --clear-needs-check-flag /var/lib/docker/devicemapper/devicemapper/metadata
# systemctl start docker.service解决办法：
# systemctl stop docker.service
# thin_check /var/lib/docker/devicemapper/devicemapper/metadata如果还有问题，则：
# thin_check --clear-needs-check-flag /var/lib/docker/devicemapper/devicemapper/metadata
# systemctl start docker.service