Bug#1041891: cloud.debian.org: Debian VM doesn’t boot with "console=hvc0" kernel parameter

[Ross Vandegrift <rvandegrift@debian.org>]

Package: cloud.debian.org
Followup-For: Bug #1041891
X-Debbugs-Cc: rvandegrift@debian.org

Control: reassign -1 src:linux

I ran into this issue, and will provide a kernel merge request.  Since qemu's
virtconsole docs barely exist, here's a simple way to reproduce.

First start a VM using a cloud image, with a console connected to /tmp/console:

    qemu-system-x86_64 \
        -drive file=debian-12-nocloud-amd64-20250428-2096.qcow2,index=0,media=disk,if=virtio \
        -machine type=q35,accel=kvm \
        -cpu host \
        -m 256m \
        -device virtio-serial,addr=5 \
        -nographic \
        -chardev socket,id=charserial0,path=/tmp/console,server=on,mux=on,wait=off \
        -device virtconsole,chardev=charserial0,name=org.lfedge.eve.console.0 \
        -serial chardev:charserial0 \
        -snapshot

Second connect with:

    socat -,rawer,escape=0x0f /tmp/console

You will see messages, but input will fail unless virtio_console happened to be
built into the initrd.

Ross