Allright. I was going to post in-depth investigation results to sum up what stepping through the code taught me (pretty much nothing, it all goes well until I lose the stepping thread due to callback/async stuff), but right before sending the text I let GDB finish the program execution, and lo and behold, some DHCP6 traffic appeared in my tcpdump terminal, and the tests finally pass. I'm thus assuming that some timeout somewhere expired while I was stepping through the code (I of course dialed up all the test timeouts).
I thus suspect that the bug lies within this call and its side-effects : https://git.launchpad.net/ubuntu/+source/systemd/tree/src/libsystemd- network/sd-dhcp6-client.c?h=applied/ubuntu/impish-proposed#n1648 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1940635 Title: systemd-networkd failing to acquire a DHCP6 lease from dnsmasq on armhf To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/glibc/+bug/1940635/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs