Re: [PATCH 5.15 000/846] 5.15.17-rc1 review

[Alan Maguire]

 On Tue, 25 Jan 2022, Naresh Kamboju wrote:

> On Tue, 25 Jan 2022 at 09:09, Daniel Díaz <daniel.diaz@xxxxxxxxxx> wrote:
> >
> > Hello!
> >
> > On 1/24/22 16:50, Daniel Díaz wrote:
> > > Hello!
> > >
> > > On 1/24/22 12:31, Greg Kroah-Hartman wrote:
> > >> This is the start of the stable review cycle for the 5.15.17 release.
> > >> There are 846 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 Wed, 26 Jan 2022 18:39:11 +0000.
> > >> Anything received after that time might be too late.
> > >>
> > >> The whole patch series can be found in one patch at:
> > >>     https://www.kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.15.17-rc1.gz
> > >> or in the git tree and branch at:
> > >>     git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-5.15.y
> > >> and the diffstat can be found below.
> > >>
> > >> thanks,
> > >>
> > >> greg k-h
> > >
> 
> Regressions detected on arm, arm64, i386, x86 on 5.15 and 5.10
> 
> > >
> > > This is one from arm64:
> > >    /builds/linux/arch/arm64/mm/extable.c: In function 'fixup_exception':
> > >    /builds/linux/arch/arm64/mm/extable.c:17:13: error: implicit declaration of function 'in_bpf_jit' [-Werror=implicit-function-declaration]
> > >       17 |         if (in_bpf_jit(regs))
> > >          |             ^~~~~~~~~~
> > >    cc1: some warnings being treated as errors
> > >    make[3]: *** [/builds/linux/scripts/Makefile.build:277: arch/arm64/mm/extable.o] Error 1
> >
> > Bisection here pointed to "arm64/bpf: Remove 128MB limit for BPF JIT programs". Reverting made the build succeed.
> 
> arm64/bpf: Remove 128MB limit for BPF JIT programs
> commit b89ddf4cca43f1269093942cf5c4e457fd45c335 upstream.
> 
> Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
> 

Thanks for the report!

This one needs slightly different handling on 5.15. Russell had a 5.15
patch for this (where BPF exception handling was still handled separately)
and I've included it below. I verified it applies cleanly to the 
linux-5.15.y branch and builds.  I'd suggest either skipping backport of 
this fix to stable completely, or just applying the below to 5.15 and
skipping further backports.

Thanks!