Upstream Ubuntu HWE should support BTF (tracking bug only)
rafaeldtinoco opened this issue · 4 comments
I'm currently working at:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1926330
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1949286
trying to make Ubuntu SRU team to accept a new package into Bionic and Focal main archive. This package is just like a dwarves-dfsg from Impish, backported to both Bionic and Focal, but it contains only the pahole-btf binary.
This way, the HWE kernel builds for those Ubuntu versions can depend on this new binary package and use /usr/bin/pahole-btf to create BTF at:
https://elixir.bootlin.com/linux/v5.14.14/source/scripts/link-vmlinux.sh#L218
The PPA bellow contains the binary package ready for MIR (Main Inclusion Request):
https://launchpad.net/~rafaeldtinoco/+archive/ubuntu/pahole-btf
With that binary, Bionic and Focal are able to encode correct BTF information within ELF (and as raw files).
Note: This is a tracking bug only (to track upstream work).
I have created an email thread, in ubuntu-devel mailing list, at:
It turns out that the DWARVES binary package has already been backported to Bionic and Focal:
dwarves-dfsg | 1.21-0ubuntu1~18.04 | bionic-proposed/universe | source
dwarves-dfsg | 1.21-0ubuntu1~20.04 | focal-updates/universe | source
dwarves-dfsg | 1.21-0ubuntu1~21.04 | hirsute-updates/universe | source
dwarves-dfsg | 1.21-0ubuntu1 | impish/universe | source
dwarves-dfsg | 1.21-0ubuntu1 | jammy/universe | source
at bug https://bugs.launchpad.net/ubuntu/+source/dwarves-dfsg/+bug/1912811
Just spoke to "xnox", from Ubuntu kernel team, and we can expect having BTF support in Ubuntu HWE kernels by the EOY (this way BTFHUB will be able to support all released kernels to that date, and won't need to support newer kernels).
dwarves-dfsg got released in Ubuntu Bionic. This means that now the kernel changes might be done in order to generate the embedded BTF files in the HWE kernels for Focal and Bionic (by EOY).
I believe this is already done by Ubuntu upstream (Bionic and Focal kernels support BTF now). The only kernel that does not support embedded BTF is 4.15 and, for that version, we're still updating btfhub-archive.