Re: [PATCH 4.19 00/37] 4.19.271-rc1 review

From: Guenter Roeck
Date: Fri Jan 27 2023 - 11:55:00 EST


On Thu, Jan 26, 2023 at 09:59:44AM +0100, Greg Kroah-Hartman wrote:
> On Mon, Jan 23, 2023 at 06:47:34PM -0800, Guenter Roeck wrote:
> > On Sun, Jan 22, 2023 at 04:03:57PM +0100, Greg Kroah-Hartman wrote:
> > > This is the start of the stable review cycle for the 4.19.271 release.
> > > There are 37 patches in this series, all will be posted as a response
> > > to this one. If anyone has any issues with these being applied, please
> > > let me know.
> > >
> > > Responses should be made by Tue, 24 Jan 2023 15:02:08 +0000.
> > > Anything received after that time might be too late.
> > >
> >
> > Build results:
> > total: 155 pass: 154 fail: 1
> > Failed builds:
> > i386:tools/perf
> > Qemu test results:
> > total: 426 pass: 426 fail: 0
> >
> > perf build failure:
> >
> > util/env.c: In function ‘perf_env__arch’:
> > cc1: error: function may return address of local variable [-Werror=return-local-addr]
> > util/env.c:166:17: note: declared here
> > 166 | struct utsname uts;
> > | ^~~
> >
> > No one to blame but me, for switching the gcc version used to build perf
> > to gcc 10.3.0 (from 9.4.0). The problem is fixed in the upstream kernel
> > with commit ebcb9464a2ae3 ("perf env: Do not return pointers to local
> > variables"). This patch applies to v5.4.y and earlier kernels.
>
> It's already in the 5.4.y tree (in release 5.4.56), and it applies to
> 4.19.y so I'll add it there, but it does not apply to 4.14.y so I would
> need a working backport for that tree if you want it there.

Turns out it won't help. It just uncovers other build failures with gcc-10
on v4.19.y, and it looks like the problem was actually introduced between
v4.14 and v4.19.

I reverted to building perf with gcc-9.

Guenter