[libvirt-users] block-commit fails

Hello, one of my VM's blockcommit job always fails. How can I find the reason? Error message is not clear. virsh snapshot-create-as --domain my-vm backup-snapshot \ --diskspec vda,file=/foo/my-vm-snapshot.img \ --disk-only --atomic --no-metadata virsh blockcommit my-vm vda --active --verbose --wait --async virsh blockjob my-vm vda --pivot internal error: unable to execute QEMU command 'block-job-complete': The active block job for device 'drive-virtio-disk0' cannot be completed