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Date:   Thu, 17 Sep 2020 09:54:43 -0400
From:   "Frank Ch. Eigler" <fche@redhat.com>
To:     Masami Hiramatsu <mhiramat@kernel.org>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Aaron Merey <amerey@redhat.com>,
        Daniel Thompson <daniel.thompson@linaro.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] perf probe: Support debuginfod client
Message-ID: <20200917135443.GA24128@redhat.com>
References: <160027467316.803747.10741549521899847231.stgit@devnote2>
 <20200916181307.GB16238@redhat.com>
 <20200916185218.GA1322686@kernel.org>
 <20200916201753.GC16238@redhat.com>
 <20200917120728.d5ecb9587ff3366b6c04228b@kernel.org>
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Hi -

> > > I need to support this in pahole...
> > 
> > pahole/dwarves use elfutils, so it already has automatic support.
> > https://sourceware.org/elfutils/Debuginfod.html
> 
> I'm still not sure that which interface of elfutils I should use
> for this "automatic" debuginfod support. Are there good documentation
> about it?

The libdwfl part of the elfutils API falls back to debuginfod lookups
internally, so e.g. systemtap had to do nothing to benefit.


> Since this series just for the kernel binary, I have to check we
> can do something on user-space binaries.

It should work identically & transparently.  If you're using one of
a few key packages of a few mainstream distros, the public debuginfod
server may already have the material available.


- FChE