Re: [PATCH v2] RISC-V: fix sifive and thead section mismatches in errata

[Conor Dooley]

On Sat, Apr 29, 2023 at 12:06:19PM -0700, Evan Green wrote:
> On Sat, Apr 29, 2023 at 10:58 AM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote:
> >
> >
> >
> > On 4/29/23 10:48, Evan Green wrote:
> > > On Sat, Apr 29, 2023 at 10:24 AM Conor Dooley <conor@xxxxxxxxxx> wrote:
> > >>
> > >> On Sat, Apr 29, 2023 at 10:21:39AM -0700, Evan Green wrote:
> > >>> On Sat, Apr 29, 2023 at 8:52 AM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote:
> > >>>>
> > >>>> When CONFIG_MODULES is set, __init_or_module becomes <empty>, but when
> > >>>> CONFIG_MODULES is not set, __init_or_module becomes __init.
> > >>>> In the latter case, it causes section mismatch warnings:
> > >>>>
> > >>>> WARNING: modpost: vmlinux.o: section mismatch in reference: riscv_fill_cpu_mfr_info (section: .text) -> sifive_errata_patch_func (section: .init.text)
> > >>>> WARNING: modpost: vmlinux.o: section mismatch in reference: riscv_fill_cpu_mfr_info (section: .text) -> thead_errata_patch_func (section: .init.text)
> > >>>>
> > >>>> Fixes: bb3f89487fd9 ("RISC-V: hwprobe: Remove __init on probe_vendor_features()")
> > >>>> Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> > >>>> Cc: Heiko Stuebner <heiko@xxxxxxxxx>
> > >>>> Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
> > >>>> Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
> > >>>> Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
> > >>>> Cc: linux-riscv@xxxxxxxxxxxxxxxxxxx
> > >>>> Cc: Conor Dooley <conor@xxxxxxxxxx>
> > >>>> Cc: Evan Green <evan@xxxxxxxxxxxx>
> > >>>> ---
> > >>>
> > >>> Thanks, Randy. I'm confused at how I didn't see that when I made the
> > >>> original fix. I feel like repro of these section mismatch errors
> > >>> depend on some other factor I'm not understanding. In any case:
> > >>
> > >> Perhaps you had a cut-down config that did not enable either of the
> > >> relevant ARCH_ options to get those errata compiled?
> > >
> > > It was weird, my original "fix" (the one listed in this Fixes tag) was
> > > needed because while the hwprobe series was clean on Palmer's branch,
> > > it generated a "section mismatch" on linux-next. As noted here, it was
> > > only with !CONFIG_MODULES, so I explicitly remember generating that
> > > config and checking it on linux-next to generate this "fix", and it
> > > came out clean. It's like the robots are getting smarter.
> > > -Evan
> >
> > I observed the problem in 8 out of 20 randconfig builds,
> > using linux-next 20230427.
> 
> Oh interesting, so not the stock k210_nommu defconfig. That makes me
> feel a little better at least.

Ohh man, that's a pretty bad config to try use (if that's your default)
for build testing stuff. The k210_mmu defconfig doesn't enable anything
other than SOC_CANAAN.
I could reproduce Randy's issue on defconfig w/ CONFIG_MODULES disabled.

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