8.3 + Debian 12 + Cloud-Init + Expanded Disk + OVMF = Kernel Panic on First Boot

[SlothCroissant]

I have a consistent repro of a kernel panic, seemingly occurring due to something between cloud-init and Proxmox running 8.3. Likely not something your average user will find, as it requires expanding a disk on first install (whereas most click-ops would be the ISO installer, I assume). My example used Ansible, found this as well on a Terraform provider: https://github.com/bpg/terraform-provider-proxmox/issues/1639, but I can also reproduce the issue entirely natively in Proxmox:

1. Download the latest debian-12-generic-amd64.qcow2 from https://cdimage.debian.org/images/cloud/bookworm/ (example is using the image uploaded on 2024-12-02 17:54)
2. Create a VM without a disk, enable cloud-init (See below for the resulting .conf to know what settings were used):
3. Import the previously-downloaded qcow2: qm disk import 100 /var/lib/vz/template/vm/debian-12-generic-amd64.qcow2 local-zfs
4. Associate/mount the disk using default settings in the VM hardware config
5. Expand the disk (I expanded mine by 64G, though my Ansible example expands by 62G) in the web UI.
6. Start the VM (below is the final .conf file)

Notes:

• A reboot/reset makes it past the kernel panic, and it *appears* as though the cloud-init is applied properly.
• The issue can be worked around by adding serial0: socket. Not sure at all why this would be.

Final VM conf:

root@pve01:~# cat /etc/pve/qemu-server/100.conf
agent: 1
bios: ovmf
boot:
cipassword: $5$3VyDlYb6$9e.xg94NF1/HWdchmwqKOtcoh3gc5h9UUDu196bmVV5
ciuser: testuser
cores: 2
cpu: host
efidisk0: local-zfs:vm-100-disk-0,efitype=4m,size=1M
ide0: local-zfs:vm-100-cloudinit,media=cdrom
ipconfig0: ip=dhcp
machine: q35
memory: 4096
meta: creation-qemu=9.0.2,ctime=1736116049
name: test
net0: virtio=BC:24:11:06:EF:F5,bridge=vmbr0,tag=10
numa: 0
onboot: 1
ostype: l26
scsi0: local-zfs:vm-100-disk-2,iothread=1,size=66G
scsihw: virtio-scsi-single
smbios1: uuid=b4913ce3-c7f0-4eaf-9fab-1ab7f7a5738b
sockets: 2
tpmstate0: local-zfs:vm-100-disk-1,size=4M,version=v2.0
vmgenid: 6091fe0e-7915-4bea-833d-161da806c628

Result:



pveversion -v:

root@pve01:~# pveversion
pve-manager/8.3.2/3e76eec21c4a14a7 (running kernel: 6.8.12-5-pve)
root@pve01:~# pveversion -v
proxmox-ve: 8.3.0 (running kernel: 6.8.12-5-pve)
pve-manager: 8.3.2 (running version: 8.3.2/3e76eec21c4a14a7)
proxmox-kernel-helper: 8.1.0
proxmox-kernel-6.8: 6.8.12-5
proxmox-kernel-6.8.12-5-pve-signed: 6.8.12-5
ceph-fuse: 17.2.7-pve3
corosync: 3.1.7-pve3
criu: 3.17.1-2
glusterfs-client: 10.3-5
ifupdown2: 3.2.0-1+pmx11
ksm-control-daemon: 1.5-1
libjs-extjs: 7.0.0-5
libknet1: 1.28-pve1
libproxmox-acme-perl: 1.5.1
libproxmox-backup-qemu0: 1.4.1
libproxmox-rs-perl: 0.3.4
libpve-access-control: 8.2.0
libpve-apiclient-perl: 3.3.2
libpve-cluster-api-perl: 8.0.10
libpve-cluster-perl: 8.0.10
libpve-common-perl: 8.2.9
libpve-guest-common-perl: 5.1.6
libpve-http-server-perl: 5.1.2
libpve-network-perl: 0.10.0
libpve-rs-perl: 0.9.1
libpve-storage-perl: 8.3.3
libspice-server1: 0.15.1-1
lvm2: 2.03.16-2
lxc-pve: 6.0.0-1
lxcfs: 6.0.0-pve2
novnc-pve: 1.5.0-1
proxmox-backup-client: 3.3.2-1
proxmox-backup-file-restore: 3.3.2-2
proxmox-firewall: 0.6.0
proxmox-kernel-helper: 8.1.0
proxmox-mail-forward: 0.3.1
proxmox-mini-journalreader: 1.4.0
proxmox-offline-mirror-helper: 0.6.7
proxmox-widget-toolkit: 4.3.3
pve-cluster: 8.0.10
pve-container: 5.2.3
pve-docs: 8.3.1
pve-edk2-firmware: 4.2023.08-4
pve-esxi-import-tools: 0.7.2
pve-firewall: 5.1.0
pve-firmware: 3.14-2
pve-ha-manager: 4.0.6
pve-i18n: 3.3.2
pve-qemu-kvm: 9.0.2-4
pve-xtermjs: 5.3.0-3
qemu-server: 8.3.3
smartmontools: 7.3-pve1
spiceterm: 3.3.0
swtpm: 0.8.0+pve1
vncterm: 1.8.0
zfsutils-linux: 2.2.6-pve1

Hardware: Dell R730XD

• CPU: Xeon E5-2683v4 (2X)
• RAM: 256GB DDR4
• Disks: 6x Toshiba 3.84TB SAS SSD in ZFS RAID 10

The kernel panic appears to be due to "Kernel panic - not syncing: Attempted to kill init!", though since I can't scroll back, I can't see more detail.