Plex LXC: Issues with hardware transcoding after restoring LXC to different node

[elospace]

I wanted to change the node running my plex server, so I restored (from PBS) to a different node (Intel N100 -> i5-12500t). However, I can't get hardware transcoding to work. I've tried setting permissions of /dev/dri/ using chmod 666, also used chown root:plex but it didn't fix the issue. I want to avoid completely setting up a new Plex LXC from scratch (using tteck).

Something I think may be notable is that on the old node, the iGPU was seen as card0 and thus 226:0, but on the new system the iGPU is card1, and therefore 226:1. I made the appropriate changes in the lxc conf file, shown below. Originally, the 226:0 was 226:1. Is there anywhere else I need to make this change in order for plex to be able to utilize the iGPU?

arch: amd64
cores: 7
features: nesting=1
hostname: plexprox
memory: 8192
net0: name=eth0,bridge=vmbr0,gw=192.168.2.254,hwaddr=BC:24:11:FF:66:04,ip=192.168.2.50/24,type=veth
onboot: 1
ostype: ubuntu
rootfs: local-nvme0:104/vm-104-disk-0.raw,size=46G
startup: up=15
swap: 4096
tags: proxmox-helper-scripts
lxc.cgroup2.devices.allow: a
lxc.cap.drop:
lxc.cgroup2.devices.allow: c 188:* rwm
lxc.cgroup2.devices.allow: c 189:* rwm
lxc.mount.entry: /dev/serial/by-id  dev/serial/by-id  none bind,optional,create=dir
lxc.mount.entry: /dev/ttyUSB0       dev/ttyUSB0       none bind,optional,create=file
lxc.mount.entry: /dev/ttyUSB1       dev/ttyUSB1       none bind,optional,create=file
lxc.mount.entry: /dev/ttyACM0       dev/ttyACM0       none bind,optional,create=file
lxc.mount.entry: /dev/ttyACM1       dev/ttyACM1       none bind,optional,create=file
lxc.cgroup2.devices.allow: c 226:1 rwm
lxc.cgroup2.devices.allow: c 226:128 rwm
lxc.cgroup2.devices.allow: c 29:0 rwm
lxc.mount.entry: /dev/fb0 dev/fb0 none bind,optional,create=file
lxc.mount.entry: /dev/dri dev/dri none bind,optional,create=dir
lxc.mount.entry: /dev/dri/renderD128 dev/dri/renderD128 none bind,optional,create=file

Relevant info:

/etc/modules (host)

vfio
vfio_iommu_type1
vfio_pci
vfio_virqfd

/etc/default/grub (host)

GRUB_DEFAULT=0
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR=lsb_release -i -s 2> /dev/null || echo Debian``
GRUB_CMDLINE_LINUX_DEFAULT="quiet initcall_blacklist=sysfb_init"
`GRUB_CMDLINE_LINUX="quiet intel_iommu=on"`

ls -l /dev/dri (on host)

drwxr-xr-x 2 root root 80 May 10 05:40 by-path
crw-rw---- 1 root video 226, 1 May 10 05:40 card1
crw-rw---- 1 root render 226, 128 May 10 05:40 renderD128

ls -l /dev/dri (on Plex lxc)

drwxr-xr-x 2 root root 80 May 10 05:40 by-path
crw-rw---- 1 root video 226, 1 May 10 05:40 card1
crw-rw---- 1 root render 226, 128 May 10 05:40 renderD128

id plex (on plex LXC)

uid=999(plex) gid=999(plex) groups=999(plex),44(video),104(render),108(ssl-cert)

EDIT:

I did a fresh install, and using a privileged LXC created using the script, hardware transcoding still doesn't work. The reason I can't do an unprivileged LXC is because I mount the NFS share in /etc/fstab, something that I cannot seem to do in unprivileged LXCs.

[tteck]

Hardware transcoding is broken in kernel 6.8.4-3-pve you can pin kernel 6.8.4-2-pve or read this post for another solution.

[elospace]

After pinning the kernel you mentioned, my issue still persists. I have also tried the solution mentioned in the post, but to no avail.

After disabling tone mapping, it seems that my iGPU is suddenly being utilized which is odd because on my old node tone mapping worked just fine. The old node is running the older kernel version as well. So I guess my issue lies with tone mapping..