Not able to build guest kernel for kata containers

[arnabghosh3654]

I want to build a guest kernel to use in my kata containers. So I have this kernel which is at path ~/linux-custom-kernel . According to the instructions, I run ./build-kernel.sh -k ~/linux-custom-kernel -f -d setup . However, despite proving the path, I get the Error: Kernel version nor provided. Later, I also tried with a kernel version-- command -- ./build-kernel.sh -v 5.4.60 -f -d setup. This gives me the error: Failed to find default config /home/user/go/src/github.com/kata-containers/packaging/kernel/configs/fragments/x86_64/.config. Any hep is much appreciated.

[devimc]

5.4 is a little bit old, try adding -s option

[arnabghosh3654]

It seems it needs a .config file at that location for it to work. However, I find no documentation regarding writing a .config file at /home/user/go/src/github.com/kata-containers/packaging/kernel/configs/fragments/x86_64/

[Jakob-Naucke]

@arnabghosh3654 build-kernel.sh setup is for downloading a suggested kernel, unpacking etc. If you have your own tree, you're one step further, at build-kernel.sh build (for Kata's patches to be applied, you should still explicitly specify a version though).

[arnabghosh3654]

@Jakob-Naucke Thanks, yes I figured that out and I tried build-kernel.sh -k ${kernel_path} build but it seems it expects a .config file at /home/user/go/src/github.com/kata-containers/packaging/kernel/configs/fragments/x86_64/.

[arnabghosh3654]

I did manage to make it work with a sample config file I found on the internet. Actually the first step i.e. the setup command I think generates a config file as well. However, since I already have the kernel, I cannot run setup and when I run the build command, it searches for the config file which isn't there.

[arnabghosh3654]

@Jakob-Naucke Also the documentation states I should either specify a kernel path or version. You seem to suggest I should specify both.

[Jakob-Naucke]

@arnabghosh3654 ah yes, sorry. The setup step can generate a config for an existing kernel with -f. ./build-kernel.sh -k /path/to/kernel -v 5.4 -f setup works for me though. You have to specify both so the script knows what patches to look for (yes, we should update the doc comment, sorry...)