kernel support below v4.5

[thugrock7]

Hey I want to use vmtest for ebpf testing and want to test my code on kernel versions below 4.6.0, so tried followed building kernels using scripts/build_kernel.sh as described in documentation. Facing no problem when building kernel >= v5.15 , but facing issues and not been able to build below that. Also in test_assets there are no kernel bzimages for versions <=4.6, any work around is possible?

[danobi]

Hi, the kernel images in test_assets and scripts in scripts/ are kinda meant for internal use (CI for this project). Obviously, you're free to use them if you'd like, but we're not making any stability guarantees there (eg removing or renaming files).

Best practice here is to use vmtest against the actual kernels/images you run in production. For example if you use ubuntu 18.04 in prod, you can try running vmtest against that full-on image

[thugrock7]

I did not have vmtest compatible kernels/images in production yet, and want to build them as to proceed for ebpf tests. So in general what is the correct way to build kernels and images that could with vmtest. I have tried passing publicly available kernels and images(built qcow2) and faced "QGA timed out". It is that i want to test ebpf code on multiple distros and older kernel versions.

[danobi]

I suppose one "correct" way is what scripts/build_kernel.sh does. You mentioned you had issues building below 5.15 -- what was the error?