On Sat, Dec 29, 2018 at 02:11:40PM +0530, Mohan R wrote:

Hi,

I was having trouble with losetup inside libvirt_lxc container. Then I found that <mknod state="on"> will provide CAP_MKNOD capability.

Even after enabling CAP_MKNOD in my container, I was not able to do 'losetup' because cgroup's device.list for my container dont have 'rwm' flags for loop devices ('b 7:* rwm' in /sys/fs/cgroup/devices/machine.slice/machine- lxc*.scope/user/*/c1.session/devices.list)

Currently I have to manually do echo "b 7:* rwm" into /sys/fs/cgroup/devices/machine.slice/machine-lxc*.scope/devices.allow file before I login into the container in order to use loop devices. It will be useful if we have a way to do this through domain xml rather than manually doing it like what I'm doing now.

I looked into rng files, but I'm not able to find a way to define 'b 7:* rwm' in xml. I just want to check with the devs if this is possible already. Otherwise I'll file one improvement bug.

Hi, For QEMU we have configuration file '/etc/libvirt/qemu.conf' where you can add some implicit devices rules using 'cgroup_device_acl'. I guess we should add the same option for LXC. There is probably no way how to do it right now so feel free to create new BUG. Pavel

I think lxc already have a way to do this through lxc.cgroup.devices.allow

Thanks, Mohan R

-- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list