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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   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
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     Miguel Ojeda <ojeda@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        rust-for-linux <rust-for-linux@vger.kernel.org>,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        "open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Geoffrey Thomas <geofft@ldpreload.com>,
        Finn Behrens <me@kloenk.de>,
        Adam Bratschi-Kaye <ark.email@gmail.com>,
        Wedson Almeida Filho <wedsonaf@google.com>
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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.

             Linus