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From:   Andrii Nakryiko <andrii.nakryiko@gmail.com>
Date:   Mon, 27 Jul 2020 15:05:11 -0700
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Subject: Re: [PATCH bpf-next v2 29/35] bpf: libbpf: cleanup RLIMIT_MEMLOCK usage
To:     Roman Gushchin <guro@fb.com>
Cc:     bpf <bpf@vger.kernel.org>, Networking <netdev@vger.kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Kernel Team <kernel-team@fb.com>,
        open list <linux-kernel@vger.kernel.org>
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On Mon, Jul 27, 2020 at 12:21 PM Roman Gushchin <guro@fb.com> wrote:
>
> As bpf is not using memlock rlimit for memory accounting anymore,
> let's remove the related code from libbpf.
>
> Bpf operations can't fail because of exceeding the limit anymore.
>

They can't in the newest kernel, but libbpf will keep working and
supporting old kernels for a very long time now. So please don't
remove any of this.

But it would be nice to add a detection of whether kernel needs a
RLIMIT_MEMLOCK bump or not. Is there some simple and reliable way to
detect this from user-space?


> Signed-off-by: Roman Gushchin <guro@fb.com>
> ---
>  tools/lib/bpf/libbpf.c | 31 +------------------------------
>  tools/lib/bpf/libbpf.h |  5 -----
>  2 files changed, 1 insertion(+), 35 deletions(-)
>

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