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Message-ID: <37e6b325-44e4-8e65-68e3-eab2943018ac@infradead.org>
Date:   Sat, 29 Apr 2023 10:58:48 -0700
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Subject: Re: [PATCH v2] RISC-V: fix sifive and thead section mismatches in
 errata
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To:     Evan Green <evan@rivosinc.com>, Conor Dooley <conor@kernel.org>
Cc:     linux-kernel@vger.kernel.org, Heiko Stuebner <heiko@sntech.de>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        linux-riscv@lists.infradead.org
References: <20230429155247.12131-1-rdunlap@infradead.org>
 <CALs-HsuG3EFBs60sgiMcPHoE1dF7mhi3GKt=AWvRPaUHAfA88Q@mail.gmail.com>
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 <CALs-HstrR3Cm3jQKt6dmfYiRRVkAVibAZDtFo0wmXz4LEvRf_A@mail.gmail.com>
From:   Randy Dunlap <rdunlap@infradead.org>
In-Reply-To: <CALs-HstrR3Cm3jQKt6dmfYiRRVkAVibAZDtFo0wmXz4LEvRf_A@mail.gmail.com>
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On 4/29/23 10:48, Evan Green wrote:
> On Sat, Apr 29, 2023 at 10:24 AM Conor Dooley <conor@kernel.org> 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@infradead.org> 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@infradead.org>
>>>> Cc: Heiko Stuebner <heiko@sntech.de>
>>>> Cc: Paul Walmsley <paul.walmsley@sifive.com>
>>>> Cc: Palmer Dabbelt <palmer@dabbelt.com>
>>>> Cc: Albert Ou <aou@eecs.berkeley.edu>
>>>> Cc: linux-riscv@lists.infradead.org
>>>> Cc: Conor Dooley <conor@kernel.org>
>>>> Cc: Evan Green <evan@rivosinc.com>
>>>> ---
>>>
>>> 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.

-- 
~Randy