modprobe: ERROR: could not insert 'v4l2loopback': Exec format error

[ghost]

I installed it with these commands:

git clone https://github.com/umlaeute/v4l2loopback.git
cd v4l2loopback
make CC=/usr/bin/gcc-8
sudo make install
sudo depmod -a

When I run

sudo modprobe v4l2loopback

I get

modprobe: ERROR: could not insert 'v4l2loopback': Exec format error

From sudo dmesg | grep -i v4l2loopback I get

[ 7100.576031] v4l2loopback: loading out-of-tree module taints kernel.
[ 7100.576130] v4l2loopback: module verification failed: signature and/or required key missing - tainting kernel

From uname -a I get

Linux anton 4.19.0-5-amd64 #1 SMP Debian 4.19.37-5+deb10u2 (2019-08-08) x86_64 GNU/Linux

From lsb_release -a I get

No LSB modules are available.
Distributor ID:	PureOS
Description:	PureOS
Release:	9.0
Codename:	amber

[wick-ed]

Hi @unicornofdeath

was the same for me (Ubuntu 18.04).
This issue's comment gave me the solving hint.
Just did make CC=/usr/bin/gcc instead of a blank make.
After that the modprobe command worked. Using the loopback to stream from OBS. :)

[ghost]

I have tried that and still get same error

[umlaeute]

I get this error

which one (probably the one from the title; but it makes a bug-report much easier to read if you don't have to jump through the page for each line)

I have tried to build from source I have download with apt-get I have tried everything and still get error

sorry, i don't understand this sentence.

I get when installed with apt-get

this doesn't look bad (as in: there's no error here).

anyhow: what did you install with apt-get?

I have tried that and still get same error

the point is you must use the same compiler as was used to build your kernel.
this might be /usr/bin/gcc (which is really just an alias to "some" compiler), it might be /usr/bin/gcc-8 (which is a specific compiler, but there's no guarantee that this is the one used to build the kernel)?

you might also consider adding information (as per the template which you seem to have ignoed), such as the kernel you are actually using, and which distribution.