Ubuntu
grub2 package

vt.handoff=7 ~broken on VM

Bug #1945873 reported by Mason Loring Bliss
6
This bug affects 1 person
Affects Status Importance Assigned to Milestone
grub2 (Ubuntu)
Triaged
Undecided
Unassigned

Bug Description

In an install made with 21.10 beta, the default settings add
vt.handoff=7 to the primary kernel command line in /boot/grub/grub.cfg.
The effect of this is that the virtual console is somewhat broken during
boot. Prompts for LUKS passphrases are hidden, and once the system is
done booting, getty prompts do not show until the user navigates to
another virtual console. (This isn't possible until the system is
booted, meaning it's not a mitigation for accessing LUKS prompt. For
that, a user can hit escape and be presented with a partially-functional
LUKS prompt.)

Attached is an example of a getty prompt not showing. This is after
hitting ESC to get a LUKS prompt so that disks could be unlocked, so
that doesn't help later boot.

The system in this case is a debootstrap-installed ZFS-on-root with an
ext4 MD-RAID1 /boot.

See original description
Revision history for this message
Mason Loring Bliss (y-mason) wrote :
Mason Loring Bliss (y-mason)
description: updated
Steve Langasek (vorlon)
affects: grub (Ubuntu) → grub2 (Ubuntu)
Revision history for this message
Mason Loring Bliss (y-mason) wrote :

Additional detail in case it's useful:

Hypervisor is Debian Buster, virt-manager, libvirt/KVM, default Spice
display, default QXL video. Legacy install, so no efifb.

Revision history for this message
Steve Langasek (vorlon) wrote :

I'm surprised to see this is the case, I thought the switch to vt1 had been completed several cycles ago.

Changed in grub2 (Ubuntu):
status: New → Triaged
Revision history for this message
Mason Loring Bliss (y-mason) wrote :

I've been lax in exercising this stuff. I tend to stick to Ubuntu LTS
hypervisors (hence hardware), and my VMs are often other systems. I only
noticed this issue because I needed a VM test environment for the un-
related ZFS root bug I was exploring. I haven't ruled out that it's an
artifact of my install method, although if it is, that itself might
indicate a missing explicit dependency somewhere. I'll try to get time
to do a vanilla install using one of the shipped installers, and I'll
report back with results.

Revision history for this message
Mason Loring Bliss (y-mason) wrote :
Revision history for this message
Mason Loring Bliss (y-mason) wrote :

I just installed Impish Indri on my Thinkpad T420 and the same issue
cropped up. This is notable in that it is a UEFI install on real
hardware. I'd expected this was a glitch that would only show up on VMs.

Revision history for this message
Mason Loring Bliss (y-mason) wrote :

Quick note, removing "splash" from the kernel command line mitigates the
issue.

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