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Subject: Re: [PATCH bpf] bpf/btf: Accept function names that contain dots
To:     Yonghong Song <yhs@meta.com>,
        Nick Desaulniers <ndesaulniers@google.com>
Cc:     Florent Revest <revest@chromium.org>,
        Andrii Nakryiko <andrii.nakryiko@gmail.com>,
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        andrii@kernel.org, song@kernel.org, yhs@fb.com,
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        haoluo@google.com, jolsa@kernel.org, nathan@kernel.org,
        trix@redhat.com, stable@vger.kernel.org
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From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <b0084c8b-fe32-f1db-ad01-961265ce00fb@iogearbox.net>
Date:   Wed, 21 Jun 2023 10:43:55 +0200
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On 6/21/23 5:28 AM, Yonghong Song wrote:
> On 6/20/23 8:07 AM, Nick Desaulniers wrote:
[...]
>> No, all kernels have this issue, when using `LLVM=1 LLVM_IAS=0`.  It's
>> more likely that someone is using that combination for branches of
>> stable that predate 4.19 (such as 4.14) but we do still try to support
>> that combination somewhat, even if we recommend just using `LLVM=1`.
>> Interop between toolchains is still important, even if "why would you
>> do that?"
> 
> Okay, yes, although 'LLVM=1' is recommended way to compiler clang
> based kernel, users can certainly do 'LLVM=1 LLVM_IAS=0' as well
> although not recommended. Then it is okay to put a bug fix in
> the commit message. Just need to clarify that
>    - > 5.10 kernel, LLVM=1 (LLVM_IAS=0 is not the default)
>      is recommended but user can still have LLVM=1 LLVM_IAS=0
>      to trigger the issue
>    - <= 5.10 kernel, LLVM=1 (LLVM_IAS=0 is the default) is
>      recommended in which case gnu as will be used.

Given this was already applied to bpf few days ago, I've just updated the
commit message to reflect the above. Agree that this is valuable info to
retain for the log.

Thanks everyone,
Daniel