From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [bpf-next V3 PATCH 0/5] tools/libbpf improvements and selftests
Date: Fri, 9 Feb 2018 12:50:22 +0100
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Cc: netdev@vger.kernel.org, Daniel Borkmann <borkmann@iogearbox.net>,
        Alexei Starovoitov <alexei.starovoitov@gmail.com>,
        wangnan0@huawei.com, jakub.kicinski@netronome.com, joe@ovn.org,
        acme@redhat.com, eric@regit.org, yhs@fb.com
To: Jesper Dangaard Brouer <brouer@redhat.com>
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On 02/09/2018 09:18 AM, Jesper Dangaard Brouer wrote:
> On Fri, 9 Feb 2018 02:32:27 +0100
> Daniel Borkmann <daniel@iogearbox.net> wrote:
> 
>> On 02/08/2018 12:48 PM, Jesper Dangaard Brouer wrote:
>>> While playing with using libbpf for the Suricata project, we had
>>> issues LLVM >= 4.0.1 generating ELF files that could not be loaded
>>> with libbpf (tools/lib/bpf/).
>>>
>>> During the troubleshooting phase, I wrote a test program and improved
>>> the debugging output in libbpf.  I turned this into a selftests
>>> program, and it also serves as a code example for libbpf in itself.
>>>
>>> I discovered that there are at least three ELF load issues with
>>> libbpf.  I left them as TODO comments in (tools/testing/selftests/bpf)
>>> test_libbpf.sh. I've only fixed the load issue with eh_frames, and
>>> other types of relo-section that does not have exec flags.  We can
>>> work on the other issues later.  
>>
>> Applied it to bpf tree, thanks Jesper!
> 
> Thank you for applying this the 'bpf' tree! -- appreciate it!

Btw, if you have a chance to send a small doc update for the
Documentation/bpf/bpf_devel_QA.txt and describe somewhere in
the LLVM section of the doc the discussed issue around
gnu/stubs-32.h with possible workarounds, that would be great.

Thanks,
Daniel