hi,all, when i use `qemu-img snapshot -c test-s sheepdog:test` to create a snapshot of sheepdog vdi,the snapshot's lock not be released.
root@hty-compute1:~/qemu# ./qemu-img create sheepdog:test 1G Formatting 'sheepdog:test', fmt=raw size=1073741824 root@hty-compute1:~/qemu# dog vdi list Name Id Size Used Shared Creation time VDI id Copies Tag test 0 1.0 GB 0.0 MB 0.0 MB 2014-12-22 17:10 7c2b25 3 root@hty-compute1:~/qemu# ./qemu-img snapshot -c test-s sheepdog:test WARNING: Image format was not specified for 'sheepdog:test' and probing guessed raw. Automatically detecting the format is dangerous for raw images, write operations on block 0 will be restricted. Specify the 'raw' format explicitly to remove the restrictions. root@hty-compute1:~/qemu# dog vdi lock list VDI | Owner node | Tag s test | IPv4 ip:172.16.17.200 port:7000 test-s when i create a snapshot ,the src vdi will be open and locked,in the function `sd_open` read the vdi inode info saved in the struct BDRVSheepdogState ,and in the function `sd_snapshot_create` the vdi inode information in the struct BDRVSheepdogState will point to an new vdi ,so when the function `sd_close` be called,the `sd_close` will try to released the lock of new vdi.In conclusion,the snapshot vdi will lock forever , so it's will be failed when i try to create a new vdi base on the snapshot. root@hty-compute1:~/qemu# ./qemu-img create -b sheepdog:test:test-s sheepdog:new-vdi qemu-img: sheepdog:new-vdi: cannot get vdi info, VDI is already locked, test 0 test-s There may be some wrong in the function`sd_snapshot_create`.but I'm not sure the root cause. Thanks, Xiaolong Xu