Okay, so it appears the source of this is the vga16fb and vgastate modules, which are loaded by default in Ubuntu, not playing well with the hyper-v frame buffer.
-- Hyper-v Screen Drawing is Slow https://bugs.launchpad.net/bugs/578944 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs