That looks like a good explanation for that bug, boot doesn't block on the network and it's likely than starting network to gdm is faster than the dhcp reply then, not sure that's a gdm bug, you should fix your dhcp server rather
-- GDM starts before home directories mounted https://launchpad.net/bugs/82617 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
