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=-10.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_MED,URIBL_BLOCKED,USER_AGENT_MUTT,USER_IN_DEF_DKIM_WL autolearn=ham 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 58E85C46460 for ; Wed, 15 Aug 2018 03:01:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0E1ED216FB for ; Wed, 15 Aug 2018 03:01:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Ir06/Lkn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0E1ED216FB Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728648AbeHOFvq (ORCPT ); Wed, 15 Aug 2018 01:51:46 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:33352 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728595AbeHOFvp (ORCPT ); Wed, 15 Aug 2018 01:51:45 -0400 Received: by mail-pf1-f195.google.com with SMTP id d4-v6so10147602pfn.0 for ; Tue, 14 Aug 2018 20:01:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=NC5t8huGFTHb/EokVDrdq/8OfB2XJ62ZP38O80MZNz0=; b=Ir06/LkncUF7/UhHuJYI8QMoYIDyiTf7YgfOU2rk+yiJjUlJTKFpto8uLi57PE3f5M Wy1CXGbA73O+E5kYrQZfE1+rP/wkhX+FCbsCxZ+W3pHmflp0Ck23mI156KK31nNb1WQb JzcpQCkOI3BSkwTBSD9yIpUZKjpzRZWufGY56zAnkEbKR/3HQM7XlmyjAXXgAz+F6y2m dnOCeUtVLnH1WlX1W+H7LaUX8BzIJTwsLHdnDTGY2dZn6StmTaBwfOZZ/NI41Dzwx4n5 lXX44Jz+ImDP31UH+/wRPlHdC9I6l1n1Oy+NLyT8bQq9d63ieI+jhv7EnnRfzQuGQjwN 2Heg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=NC5t8huGFTHb/EokVDrdq/8OfB2XJ62ZP38O80MZNz0=; b=a2ZBaogMPIcW/kHy001vzLNxJQ1p7YUD+7GzRTkDB31lzkklomNnquEU/txeDAXaD6 zr/w1d+foRSZ4v0tOa/cwjW6C33oLvA6IGG+EEIdARBZoewYR2xWN2UdN/wcPcDZrUpl sPCHeUbfa/focG/fDN/FLK8XoPyPDRet3ZGTY51vrwv0WmCid7StfAsZIEV2ztPDhscJ pQTTMeXGxXmrE/KT2UOTO1zSfvtVYIjzaTo3fWa0qrIIdxmFhQn50dfJCA1HCLx9kauW vNOum/jnsEqHanmkGxVm9KAiw7FiWbanhRLpq5xf3/P9/VBcfN4IjxzVy5RsRkOtLB6j aukA== X-Gm-Message-State: AOUpUlFdIX3mhtnZvnCaUkgzhUDrA86fcn3eFMSSM08tmGEiSFY0R2wD ikTZsuJ0rmsSYWfISE5Q10QQAmqMpZ8= X-Google-Smtp-Source: AA+uWPy17MMX6iYZYolscloYln+tTPdcqO16gGeD3youe3vbnTtlrnpmF/iNiJk70ucM9mpw6FrcWw== X-Received: by 2002:a63:8c0b:: with SMTP id m11-v6mr23506893pgd.372.1534302094330; Tue, 14 Aug 2018 20:01:34 -0700 (PDT) Received: from localhost ([2620:0:1000:1601:3aef:314f:b9ea:889f]) by smtp.gmail.com with ESMTPSA id c85-v6sm43656061pfd.110.2018.08.14.20.01.32 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 14 Aug 2018 20:01:33 -0700 (PDT) Date: Tue, 14 Aug 2018 20:01:32 -0700 From: Joel Fernandes To: LKML , wangnan0@huawei.com, "open list:BPF (Safe dynamic programs and tools)" , Alexei Starovoitov , acme@kernel.org, Chenbo Feng , Jakub Kicinski Subject: Re: samples don't build on v4.18 Message-ID: <20180815030132.GA204101@joelaf.mtv.corp.google.com> References: <20180815012054.GA70201@joelaf.mtv.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 14, 2018 at 06:22:21PM -0700, Joel Fernandes wrote: > Forgot to add the patch author, doing so now. thanks > > On Tue, Aug 14, 2018 at 6:20 PM, Joel Fernandes wrote: > > > > Hi, > > When building BPF samples on v4.18, I get the following errors: > > > > $ cd samples/bpf/ > > $ make > > > > Auto-detecting system features: > > ... libelf: [ OFF ] > > ... bpf: [ OFF ] > > > > No libelf found > > Makefile:213: recipe for target 'elfdep' failed > > ----------- > > > > I bissected it down to commit 5f9380572b4bb24f60cd492b1 > > > > Author: Jakub Kicinski > > Date: Thu May 10 10:24:39 2018 -0700 > > > > samples: bpf: compile and link against full libbpf > > --------- > > > > Checking out a kernel before this commit makes the samples build. Also I do > > have libelf on my system. > > > > Any thoughts on this issue? There is some weirdness going on with my kernel tree. If I do a fresh clone of v4.18 and build samples, everything works. However if I take my existing checkout, do a: git clean -f -d make mrproper Then I try to build the samples, I get the "No libelf found". Obviously the existing checked out kernel tree is in some weird state that I am not yet able to fix. But atleast if I blow the whole tree and clone again, I'm able to build... Is this related to the intermittent "No libelf found" issues that were recently discussed? - Joel