With libvirt 6.9.0, qemu 5.1.0, and following configurations:

libvirt:

key_file = "/etc/ssl/libvirt/server.lan.key"

cert_file = "/etc/ssl/libvirt/server.lan.crt"
ca_file = "/etc/ssl/libvirt/ca.crt"

log_filters="3:remote 4:event 3:util.json 3:rpc 1:*"
log_outputs="1:file:/var/log/libvirt/libvirtd.log"

qemu:

default_tls_x509_cert_dir = "/etc/ssl/qemu"
default_tls_x509_verify = 1

migration with tls:

virsh # migrate vm1 qemu+tls://server2.lan/system --persistent --undefinesource --copy-storage-all --verbose --tls

never succeeds. Progress stops typically at high progress amounts (95%-98%), and network traffic drastically drops as well (from 1 gbps+ to nothing). domjobinfo progress also stops. Without --tls migrations succeed without issues without any other changes to hosts or configurations.

Logs of failed migration:

Source: https://drive.google.com/file/d/1d0dJumicW0TUdG1osNxNnWWiYpfAaIb_/view?usp=sharing

Destination: https://drive.google.com/file/d/1d0dJumicW0TUdG1osNxNnWWiYpfAaIb_/view?usp=sharing

Same exact hosts, successful migration logs (without --tls):

Source: https://drive.google.com/file/d/1d0dJumicW0TUdG1osNxNnWWiYpfAaIb_/view?usp=sharing

Destination: https://drive.google.com/file/d/1EWkCkSBhj76T05k86QjdL-6icJyruK5-/view?usp=sharing

Should I report this as a bug or is there an issue with my configuration?