Instance data deleted on shared storage after failed evacuate (queens)

[Jacolex]

Hi
The issue was experienced after one of compute nodes crashed. Then, after reboot of compute node, few instances was restarted, but rest of instances failed to start with error:
"Failed to get "write" lock
Is another process using the image?"

I tried to evacuate one instance to another host:
nova evacuate instance host2

After that nova compute on destination host throwed the same error:
Setting instance vm_state to ERROR: libvirtError: internal error: process exited while connecting to monitor: 2018-10-10T10:16:09.816477Z qemu-system-x86_64: -drive file=/var/lib/nova/instances/ed7760a8-3008-4feb-83f3-3b753b0e7d6e/disk,format=qcow2,if=none,id=drive-virtio-disk0,cache=none: Failed to get "write" lock
Is another process using the image?

Regardless of reason of this issue, the whole directory of the instance was gone from shared nfs, so /var/lib/nova/instances/ed7760a8-3008-4feb-83f3-3b753b0e7d6e was removed with instance disk.

Then I reproduced the error. After backup of disk file, evacuate and restore instance directory with disk file, the instance was started successfully.