Hi, I’m trying to install v4l2loopback devices, but when modprobing no /dev/videoX device is created, and modprobe also doesnt give any error.
Here’s a full log from the terminal:
drakorg@dev-jp43:~$ sudo apt list -i | grep -i v4l2loopback WARNING: apt does not have a stable CLI interface. Use with caution in scripts. drakorg@dev-jp43:~$ sudo apt install v4l2loopback-dkms Reading package lists... Done Building dependency tree Reading state information... Done The following packages were automatically installed and are no longer required: libavdevice57 libtext-charwidth-perl libtext-wrapi18n-perl module-assistant v4l-utils Use 'sudo apt autoremove' to remove them. Suggested packages: v4l2loopback-utils The following NEW packages will be installed: v4l2loopback-dkms 0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded. Need to get 23,1 kB of archives. After this operation, 112 kB of additional disk space will be used. Get:1 http://ports.ubuntu.com/ubuntu-ports bionic/universe arm64 v4l2loopback-dkms all 0.10.0-1ubuntu1 [23,1 kB] Fetched 23,1 kB in 1s (34,3 kB/s) debconf: delaying package configuration, since apt-utils is not installed Selecting previously unselected package v4l2loopback-dkms. (Reading database ... 171277 files and directories currently installed.) Preparing to unpack .../v4l2loopback-dkms_0.10.0-1ubuntu1_all.deb ... Unpacking v4l2loopback-dkms (0.10.0-1ubuntu1) ... Setting up v4l2loopback-dkms (0.10.0-1ubuntu1) ... Loading new v4l2loopback-0.10.0 DKMS files... It is likely that 4.9.140-tegra belongs to a chroot's host Building for 4.15.0-20-generic and 4.9.140-tegra Building initial module for 4.15.0-20-generic Done. v4l2loopback: Running module version sanity check. - Original module - No original module exists within this kernel - Installation - Installing to /lib/modules/4.15.0-20-generic/updates/dkms/ depmod... DKMS: install completed. Building initial module for 4.9.140-tegra Done. v4l2loopback: Running module version sanity check. - Original module - No original module exists within this kernel - Installation - Installing to /lib/modules/4.9.140-tegra/updates/dkms/ depmod... DKMS: install completed. drakorg@dev-jp43:~$ sudo modprobe v4l2loopback devices=8 drakorg@dev-jp43:~$ ls -la /dev/video* ls: cannot access '/dev/video*': No such file or directory drakorg@dev-jp43:~$
As you can see modprobe doesnt create the devices … and I have no clue on where to start digging.
For the record, /dev/video0 had been created successfully before, and I could use it with no problem, until a moment where it started to give an error (ioctl write error something), so I sudo apt removed it, hoping I would be able to recreate them, but it didn’t work.
I also see on the logs that it refers to two versions, 4.9 and 4.15 and that it says something about one of them probably belonging to a chroot environment, but I’ve no clue what that means, or if it’s normal.
If anyone has any pointer on where to start looking I’d really appreciate it.
The workaround if I don’t manage to make it work again, reinstall from scratch, but if I can avoid that, great.