[SOLVED] LXC and device passthrough

[yarii]

Hi all,

I tried to passthrough /dev/ttyS0 and /dev/ttyUSB0 to container by:

lxc-device add -n 204 /dev/ttyS0
lxc-device add -n 204 /dev/ttyUSB0

It works well.

For making it avaible after container restart I added this to /var/lib/lxc/204/config by adding lines:
lxc.cgroup.devices.allow = c 4:64 rwm
lxc.cgroup.devices.allow = c 188:0 rwm

After container restart there is old config without changes.

How to properly do /dev/USB and /dev/ttyS0 passthrough?

Regards.
JK

 

[t.lamprecht]

lxc.cgroup.devices.allow = c 4:64 rwm
lxc.cgroup.devices.allow = c 188:0 rwm

Add this to /etc/pve/nodes/<nodename>/lxc/204.conf
which is the "real" config from PVEs view, then it should work.

 

[yarii]

Do I need to do something more?

After rebooting container ...
204#
ls -la /dev/ | grep ttyS0
doesn't show anything.

 

[yarii]

I added this:
mknod /dev/ttyS0 c 4 64
chown root.dialout /dev/ttyS0
chmod 0644 /dev/ttyS0

to my rc.local.

And it is OK right now.

 

[fabian]

I did:
mknod /dev/ttyS0 c 4 64
chown root.dialout /dev/ttyS0
chmod 0644 /dev/ttyS0

It is OK right now.

the "lxc.cgroup.devices.allow" lines only tell lxc to setup the container's cgroup to allow access to or creation of the specified device nodes (see https://www.kernel.org/doc/Documentation/cgroup-v1/devices.txt for the gory details ). You need to create the device nodes yourself in the container (either manually, or using an init script, or using an autodev hook).

 

[yarii]

I thought that proxmox-ve scripts do it automaticly.

 

[t.lamprecht]

Maybe that is of use for you:
https://forum.proxmox.com/threads/passthrough-usb-from-host-to-lxc.23856/#post-120617