From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8BD64FC6196 for ; Fri, 8 Nov 2019 21:43:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B56B215EA for ; Fri, 8 Nov 2019 21:43:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732843AbfKHVnI convert rfc822-to-8bit (ORCPT ); Fri, 8 Nov 2019 16:43:08 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:38818 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732101AbfKHVnI (ORCPT ); Fri, 8 Nov 2019 16:43:08 -0500 Received: from localhost (unknown [IPv6:2601:601:9f00:1e2::d71]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id D74BA153873A8; Fri, 8 Nov 2019 13:43:07 -0800 (PST) Date: Fri, 08 Nov 2019 13:43:07 -0800 (PST) Message-Id: <20191108.134307.2153170175114525963.davem@davemloft.net> To: toke@redhat.com Cc: daniel@iogearbox.net, ast@kernel.org, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, brouer@redhat.com, andrii.nakryiko@gmail.com, netdev@vger.kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH bpf-next v2 3/6] libbpf: Propagate EPERM to caller on program load From: David Miller In-Reply-To: <157324878850.910124.10106029353677591175.stgit@toke.dk> References: <157324878503.910124.12936814523952521484.stgit@toke.dk> <157324878850.910124.10106029353677591175.stgit@toke.dk> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Fri, 08 Nov 2019 13:43:08 -0800 (PST) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Toke Høiland-Jørgensen Date: Fri, 08 Nov 2019 22:33:08 +0100 > From: Toke Høiland-Jørgensen > > When loading an eBPF program, libbpf overrides the return code for EPERM > errors instead of returning it to the caller. This makes it hard to figure > out what went wrong on load. > > In particular, EPERM is returned when the system rlimit is too low to lock > the memory required for the BPF program. Previously, this was somewhat > obscured because the rlimit error would be hit on map creation (which does > return it correctly). However, since maps can now be reused, object load > can proceed all the way to loading programs without hitting the error; > propagating it even in this case makes it possible for the caller to react > appropriately (and, e.g., attempt to raise the rlimit before retrying). > > Acked-by: Song Liu > Signed-off-by: Toke Høiland-Jørgensen Acked-by: David S. Miller