Return error for migrate cancel, when migration status is not MIG_STATE_SETUP or MIG_STATE_ACTIVE. Thus, libvirt can can perceive the operation fails.
Signed-off-by: zengjunliang <zengjunliang@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com>
I think this is done on purpose, because canceling migration is racy. Instead, libvirt should do "query-migrate" and check if the migration was completed or canceled.
Can you please give more details at how you are triggering the problem with libvirt? I think Paolo is probably right - the bug is more likely to be in libvirt not expecting the race and not recovering correctly when the race occurs, than it is to be in changing qemu's state algorithm.
When the migration progress reaches 100%, and the migration status becomes MIG_STATE_COMPLETED in Qemu. It will take some time which from MIG_STATE_COMPLETED to the migration thread resources are recovered. If we cancel the migration at this moment, the migrate_fd_cancel function will break directly without reporting error code. Then, libvirt considers the cancle operation a success, contrary facts.
Ping... Best regards, -Gonglei