Re: [libvirt] [PATCH v2 00/14] Add TLS support for migration

Hmm, I see this is a limitation of the migrate-set-parameters method. You can set new parameters for tls_creds / tls_hostname, but you can't fully delete the old parameters. The tls_hostname is only set on the source host of the migration and that VM will be killed off upon successful migration. The problem only arises if you have a migration that fails, and you then try to migrate that same VM again later, *and* you don't have tls_hostname set. I don't think that'd hit libvirt, since libvirt will always need to set tls-hostname as it uses fd: migrate method. IOW, I don't see any need to be able to clear tls-hostname when used with libvirt.

For TLS creds it would be a problem if we do a TLS migration and then need to migrate the target QEMU again later, but don't want TLS used, as that would require us to fully clear the tls_creds parameter. At best we can set it to empty string, which is not good enough. So seems we need a QEMU fix here.