I have been able to eliminate the focal 5.4.0-26-generic kernel packages as the origin of this bug. Manually installing those onto an installation of Ubuntu 19.10, produced a fully functional boot. More importantly the recovery mode boot from grub worked fine. So the problem under 20.04 would appear to be something outside of the kernel itself.
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-meta in Ubuntu. https://bugs.launchpad.net/bugs/1873965 Title: booting into recovery mode hangs under 20.04 Status in linux-meta package in Ubuntu: New Bug description: On a 2008 MacPro with GTX680 under Ubuntu 20.04, selecting the recovery mode from grub hangs on loading of the ramdisk with the Recovery Menu dialog never appearing. This problem doesn't exist for a fresh install of Ubuntu 18.04 updated to the current package updates. In that case, the Recovery Menu appears as expected. This bug in Ubuntu 20.04 was reproduced for both an existing Ubuntu 19.10 installation dist-upgraded to Ubuntu 20.04 as well as for a fresh install of Ubuntu 20.04. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-meta/+bug/1873965/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
