bug#70962: Add BTF support to kernel, sysdig and dependents, zstd-compressed modules

[Maxim Cournoyer]

Hi,

Maxim Cournoyer <maxim.cournoyer@gmail.com> writes:

>  This series adds BTF (Berkeley Type Format) support to our kernel, catching 
> up
>  with other main distributions in enabling embedded BPF (Berkeley Packet
>  Filter) programs.
>
>  This was motivated by packaging 'sysdig', a system introspection application
>  that can make use of BTF.  Adding BTF does incur some size increase; with
>  'linux-libre' package going up from 132 MiB to 164 MiB (24%).  This is later
>  somewhat mitigated by using Zstd compressed (at maximum level, 19) kernel
>  modules, which brings the kernel size back down to 144 MiB, which corresponds
>  to a more reasonable 9% increase from before this series.  The BPF kernel
>  variant we were carrying is removed as proper BPF support will now exists in
>  our main kernel.
>
>  That's it!  I hope you enjoy using 'csysdig' to keep track of the syscalls 
> and
>  IO usage of your process/threads.
>  END
>
>
>
> Maxim Cournoyer (14):
>   gnu: grpc: Modernize.
>   gnu: grpc: Propagate abseil-cpp-cxxstd11.
>   gnu: Add valijson.
>   gnu: libbpf: Use gexps.
>   gnu: libbpf: Update to 1.4.1.
>   gnu: Add falcosecurity-libs.
>   gnu: Add sysdig.
>   gnu: Add dwarves.
>   gnu: make-linux-libre*: Set KBUILD_BUILD_VERSION for reproducibility.
>   gnu: make-linux-libre*: Run install targets in parallel.
>   gnu: linux: Turn %default-extra-linux-options into a procedure.
>   gnu: linux-libre: Enable BTF debug info.
>   gnu: linux-libre: Enable Zstd compression of kernel modules.
>   gnu: linux-libre-with-bpf: Deprecate in favor of linux-libre.

I've used this for more than a week, and I haven't noticed any issue.

Merged with 7fd2f2e6fd3725c6dfe7df61a20269e6c7a46733 and the subsequent
commits.

-- 
Thanks,
Maxim