Re: [PATCH v5 0/2] kbuild: distributed build support for Clang ThinLTO

Nathan Chancellor
2025-12-04T17:50:01Z

Hi Rong,

On Tue, Oct 28, 2025 at 06:28:20PM +0000, xur@google.com wrote:

First of all, my apologies for taking so long to get to testing and
reviewing this patchset.

> Rong Xu (2):
> kbuild: move vmlinux.a build rule to scripts/Makefile.vmlinux_a
> kbuild: distributed build support for Clang ThinLTO
>
> .gitignore | 2 +
> Makefile | 25 +++++-------
> arch/Kconfig | 19 +++++++++
> scripts/Makefile.lib | 7 ++++
> scripts/Makefile.thinlto | 40 ++++++++++++++++++
> scripts/Makefile.vmlinux_a | 83 ++++++++++++++++++++++++++++++++++++++
> scripts/mod/modpost.c | 15 +++++--
> 7 files changed, 174 insertions(+), 17 deletions(-)
> create mode 100644 scripts/Makefile.thinlto
> create mode 100644 scripts/Makefile.vmlinux_a

Overall, this seems reasonable from a high level perspective. I have
been testing it with my arm64 and x86_64 distribution configurations for
the past couple of days and I have not noticed any issues.

Did you take a look at the robot report from patch 2?

https://lore.kernel.org/202511052257.Bb85ptQG-lkp@intel.com/

It seems like it could be caused by different optimizations?

I plan to take a more in-depth look at the implementation after I am
back home from Plumbers in a couple of weeks (just to make sure I
understand it from a maintainer's perspective). Based on that, I will
either apply it to kbuild-next for 6.20/7.0 or ask for further
interations, while still aiming to get it into that release.

Cheers,
Natha