It booted at least. I'll try your suggestions as soon as I can, I'm
progressing slower than ever, concentration is somewhat lapse still....

Thanks.
Best regards
Michael

On Tue, Jan 11, 2022, 10:51 Christophe Leroy <christophe.leroy@csgroup.eu>
wrote:

>
>
> Le 11/01/2022 à 10:32, Mike a écrit :
> > I managed to fix it in the end, patch attached, though i should have
> > done a $(call cc-option-, -maltivec, -mabi=altivec) in the
> > arch/powerpc/mm/Makefile
> >   I wrongly assumed that the manual i had downloaded at 4.44am was for
> > 32bit ppc only and found ptesync to be ppc64 only.
> >
> > binutils-2.37.50 - GNU assembler version 2.37.50 (powerpc-linux-gnu)
> > using BFD version (GNU Binutils for Debian) 2.37.50.20220106
> > gcc version 11.2.0 (Debian 11.2.0-13)
> > ld.lld is missing but with LLVM/CLANG and LD=ld.bfd
> > arch/powerpc/kernel/vdso32/gettimeofday.S:72:8:
> > error: unsupported directive '.stabs'    .stabs
> > "_restgpr_31_x:F-1",36,0,0,_restgpr_31_x; .globl _restgpr_31_x;
> > _restgpr_31_x:
> >
> > Attached the config i'm using, and the debian config 5.15.0-2. It's
> > still building.
>
> Ok, I tried with your config on my Fedora Core 35 where I have:
>
> powerpc64-linux-gnu-gcc (GCC) 11.2.1 20210728 (Red Hat Cross 11.2.1-1)
> GNU ld version 2.37-3.fc35
>
>  From packages:
> - binutils-powerpc64-linux-gnu-2.37-3.fc35.x86_64
> - gcc-powerpc64-linux-gnu-11.2.1-1.fc35.x86_64
>
> And I don't have the problems you mention, so it must be something
> special with Debian GCC.
>
>
> Your change regarding ptesync is probably OK but is fragile I think,
> because for instance there is also a 'ptesync' in
> arch/powerpc/mm/pageattr.c and probably many other places.
>
> Also please prefer CONFIG_PPC64 to __powerpc64__
>
> Regarding the DSSALL issue, the following commit will probably help:
>
> d51f86cfd8e3 ("powerpc/mm: Switch obsolete dssall to .long")
>
> Regarding the .stabs with LLVM there is a patch at
>
> https://patchwork.ozlabs.org/project/linuxppc-dev/patch/68932ec2ba6b868d35006b96e90f0890f3da3c05.1638273868.git.christophe.leroy@csgroup.eu/
>
> Thanks
> Christophe
>
>
>
> >
> > Cheers
> > Michael
> >
> > On Tue, 11 Jan 2022 at 07:20, Christophe Leroy
> > <christophe.leroy@csgroup.eu> wrote:
> >>
> >>
> >>
> >> Le 10/01/2022 à 13:32, Mike a écrit :
> >>> Hey, so I originally sat down to compile the fast headers V2 patch, but
> >>> quickly discovered other things at play, and grabbed 5.16.0 a few hours
> >>> after it lifted off,  arch/powerpc/mm/mmu_context.c I had to
> >>> specifically say had to include -maltivec or it barfed on a 'dssall',
> >>> I'm fine with that, I've spent years in kernel land, I can deal with
> >>> that, then came arch/powerpc/lib/step.c with the ptesync. This seems
> >>> like a totally normal instruction that shouldn't need any extra flags
> or
> >>> anything, yet the assembler throws up, and no flag I can think of fixes
> >>> it. This is a G4 7447. I reverted back to the Debian 5.15. defconfig
> >>> before dropping this mail as I had tweaked my config to be more G4.
> >>>
> >>
> >> Hi Mike,
> >>
> >> Can you provide a bit more details about your setup and config ?
> >>
> >> Are you using GCC or LLVM ?
> >> What version of GCC and BINUTILS or what version of LLVM ?
> >>
> >> What is DEBIAN defconfig ? Does it correspond to one of the standard
> >> mainline kernel defconfigs ? If not can you provide it ?
> >>
> >> Thanks
> >> Christophe