Building and installing kernel with new flags

[Elkins]

Hello,

I recently received a Turris Omnia router to test stuff and fool around a bit. I followed this tutorial : https://openwrt.org/toh/turris/turris_omnia to install the latest version of OpenWRT on it and it works like a charm.

Now, i realized that the OpenWRT image I used is shipped wit a kernel without the CONFIG_DEBUG_INFO_BTF flag enabled. Sadly, I need it to test some eBPF features. I already rebuilt the kernel from source using the exact same version, but I'm kind of stuck at the installation phase.

From what I understood while digging this forum, it is not recommended to build the kernel by yourself. But as I mentioned above, this is just a test environment, I do not intend to deploy it on any production network. And I'm not afraid to brick my router as I can easily re-flash it from a backup image I made. So I guess it's not too bad if I end up with an "unstable" environment.

So, is there a way for me to install a kernel with (slightly) different flags from the official release ?

[hnyman]

@Elkins

is there a way for me to install a kernel with (slightly) different flags from the official release ?

Yes, if you compile the kernel into your personal firmware and flash the firmware.
There is no supported way of upgrading just the kernel.

[Elkins]

Thanks for the indication, that led me to follow this tutorial : https://openwrt.org/docs/guide-developer/toolchain/use-buildsystem and it solved my problem.