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From:   ebiederm@xmission.com (Eric W. Biederman)
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Miguel Ojeda <ojeda@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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        Geoffrey Thomas <geofft@ldpreload.com>,
        Finn Behrens <me@kloenk.de>,
        Adam Bratschi-Kaye <ark.email@gmail.com>,
        Wedson Almeida Filho <wedsonaf@google.com>
References: <20210704202756.29107-1-ojeda@kernel.org>
        <20210704202756.29107-3-ojeda@kernel.org>
        <CAKwvOdmhRuF5eTZ2ztZBrL6BvDkA57B7OfVuvCaEMfV8nkLXCQ@mail.gmail.com>
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Date:   Wed, 14 Jul 2021 15:09:01 -0500
In-Reply-To: <CAHk-=whzXv=Fu7dQshSTyd9H1-JS5=gyKwW-GMNGccAKs4Mwpg@mail.gmail.com>
        (Linus Torvalds's message of "Wed, 14 Jul 2021 12:04:08 -0700")
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Subject: Re: [PATCH 02/17] kallsyms: increase maximum kernel symbol length to 512
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Linus Torvalds <torvalds@linux-foundation.org> writes:

> On Wed, Jul 14, 2021 at 11:20 AM Nick Desaulniers
> <ndesaulniers@google.com> wrote:
>>
>> Do we demangle rust symbols when printing a trace from a warn/panic?
>> That would be nice.
>
> I think it would be pretty much required. Otherwise stack traces are
> going to be very very painful.
>
> In fact, I'm starting to think that Willy is right: we should use
> hashes for the "real" symbol name, and have demangled names for
> printing, and at no point would the kernel actually want or need to
> have the nasty mangled names.
>
> (This wouldn't be rust-specific - using hashes for module linking
> sounds like a good diea for C code as well, even if the de-mangled
> names for printing are then the regular ones)
>
> Anybody interested in looking into that? It would make this "big
> kernel symbols" patch immaterial.

Are you thinking the hashed kernel symbols need to have their types
included in the hash?  Or is this just a hash to make the names a
managable size?

Eric