Re: i386: tinyconfig: perf_event.h:838:21: error: invalid output size for constraint '=q'

[Nathan Chancellor <nathan@kernel.org>]

Hi Naresh,

On Sun, Oct 24, 2021 at 08:05:01AM +0530, Naresh Kamboju wrote:
> Following i386 tinyconfig  clang-13 and clang-nightly failed on
> stable-rc queue/5.4.
> 
> Fail (119 errors) with status message
> 'failure while building tuxmake target(s): default': ea3681525113
>  ("net: enetc: fix ethtool counter name for PM0_TERR")
>  i386 (tinyconfig) with clang-nightly
> @ https://builds.tuxbuild.com/1zvtvNS4eyYkOMiXtFgR7n1k0Yc/
> 
> 
> make --silent --keep-going --jobs=8
> O=/home/tuxbuild/.cache/tuxmake/builds/current ARCH=i386
> CROSS_COMPILE=i686-linux-gnu- HOSTCC=clang CC=clang
> In file included from /builds/linux/arch/x86/events/amd/core.c:12:
> /builds/linux/arch/x86/events/amd/../perf_event.h:838:21: error:
> invalid output size for constraint '=q'
>         u64 disable_mask = __this_cpu_read(cpu_hw_events.perf_ctr_virt_mask);
> 
> build link,
> https://builds.tuxbuild.com/1zvtvNS4eyYkOMiXtFgR7n1k0Yc/
> 
> Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>

I am surprised this is being reported as a new issue for 5.4, as it
should have always had this error [1]. We did not fix this until 5.9
[2], meaning that 5.10 and beyond is fine. The series that did fix it
was rather long so I am not sure it is suitable for stable. My
recommendation is to disable i386 testing for 5.4 and earlier with
clang.

[1]: https://github.com/ClangBuiltLinux/linux/issues/194
[2]: https://git.kernel.org/linus/ba77c568f3160657a5f7905289c07d18c2dfde78

Cheers,
Nathan