As explained above, after extensive debugging in January, no obvious issue in GRUB was found, and this seems like a bug in the firmware network driver that causes it to lock up.
If new information comes about, I am open to revisiting this, but I am closing this for now. ** Changed in: grub2 (Ubuntu) Status: Incomplete => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2044549 Title: pxe boot on arm64 stopped working To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/2044549/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs