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Date:   Fri, 18 Oct 2019 21:11:27 +0200
From:   Daniel Borkmann <daniel@iogearbox.net>
To:     John Fastabend <john.fastabend@gmail.com>
Cc:     andriin@fb.com, ast@kernel.org, netdev@vger.kernel.org,
        bpf@vger.kernel.org
Subject: Re: [bpf-next PATCH] bpf: libbpf, add kernel version section parsing
 back
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On Fri, Oct 18, 2019 at 07:41:26AM -0700, John Fastabend wrote:
> With commit "libbpf: stop enforcing kern_version,..." we removed the
> kernel version section parsing in favor of querying for the kernel
> using uname() and populating the version using the result of the
> query. After this any version sections were simply ignored.
> 
> Unfortunately, the world of kernels is not so friendly. I've found some
> customized kernels where uname() does not match the in kernel version.
> To fix this so programs can load in this environment this patch adds
> back parsing the section and if it exists uses the user specified
> kernel version to override the uname() result. However, keep most the
> kernel uname() discovery bits so users are not required to insert the
> version except in these odd cases.
> 
> Fixes: 5e61f27070292 ("libbpf: stop enforcing kern_version, populate it for users")
> Signed-off-by: John Fastabend <john.fastabend@gmail.com>

Applied, thanks!