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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 920CDC433F5 for ; Mon, 23 May 2022 11:09:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234514AbiEWLJy (ORCPT ); Mon, 23 May 2022 07:09:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50906 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234451AbiEWLJy (ORCPT ); Mon, 23 May 2022 07:09:54 -0400 Received: from mail-wm1-x333.google.com (mail-wm1-x333.google.com [IPv6:2a00:1450:4864:20::333]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F987326D1 for ; Mon, 23 May 2022 04:09:52 -0700 (PDT) Received: by mail-wm1-x333.google.com with SMTP id bg25so8511788wmb.4 for ; Mon, 23 May 2022 04:09:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=99YcopuxEHSV216JNe5FsgqI+gRxWQSyQwsE3zpuh2Y=; b=BBKu3I/ET2v+HPBt9vTcV3TA0IwtGnt4/j/iNss/AQ0oFWrd6C02gRXpniLS6Kz30q 200f7jZdTx3WozJzoV8qxRzE/oylamRODPnQ8C3lhC/n097VXBNft3r8mStM8fazMnOt 2CrZmyBD12Diito5QxaG7kGlEwygUQdv6cXu6ek+ZYPBSP0KX5ofIeZoAGsN6LvmJBXj wHh/QNnybUJ7Gto49gHMOB8hVM2rPfzUzBCR+j/Uf2pFiZdNbLPILPnUYF9FYsZRGpZ4 NeUuwxxB6PXmi2XyMyfEdyq5AAo/3c1SMocvi+h6Ooqp/NpSVBUCgGajsH0tSWciQwUW KUhA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=99YcopuxEHSV216JNe5FsgqI+gRxWQSyQwsE3zpuh2Y=; b=sDHELTceUtsnY2KCFP0X1Az/pRFKoQNvG7K6MqAPcF+cusF9NNx4OoqMcMBxMuWcWl o0vZ5/KbjGMV/zfFnXK0poEP8kuW3it6FPafL2zG1qF6MeqyqZQQ9d/aINRHwtu2bq6K sCj33Lxi1iJwrcsDcIDVH/dQHW/V+73nDUpi8RRKh9GPEZGPePaMVijegyaCtZzqerNB 3C+Hvrz2YAgsfdPZezV3LRqtd3XR6y2OBtF6zNkWGLp7Q1QHsBDzxbdP6WnQh81zUVur iG5np96vptIdr2fVC91sMN/xFS1159QgkCuLxMubTrhcId2w/VKvH2xTq4wILDvEhUEJ eoUg== X-Gm-Message-State: AOAM532LTdckQCWFX47MMN5DTU1guhpVO9nft6XANQAD0+qGyLwrJ3VC CCUllo83mkGAwzbLaD/z8Pk= X-Google-Smtp-Source: ABdhPJxSXjryZS/U97ADqi33yoAB4RKASlwoGcr/onihR0hI6+ZYWys7IE9KfXBYGgjsBKtl1Pb3hA== X-Received: by 2002:a7b:c933:0:b0:397:463c:cc82 with SMTP id h19-20020a7bc933000000b00397463ccc82mr7699580wml.187.1653304191110; Mon, 23 May 2022 04:09:51 -0700 (PDT) Received: from krava (net-93-65-240-241.cust.vodafonedsl.it. [93.65.240.241]) by smtp.gmail.com with ESMTPSA id 186-20020a1c02c3000000b003973e27b789sm7285429wmc.27.2022.05.23.04.09.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 May 2022 04:09:50 -0700 (PDT) From: Jiri Olsa X-Google-Original-From: Jiri Olsa Date: Mon, 23 May 2022 13:09:47 +0200 To: Thomas Richter Cc: "linux-perf-use." , Arnaldo Carvalho de Melo , Jiri Olsa , Sumanth Korikkar , Heiko Carstens , vasily Gorbik , Ian Rogers , Ilya Leoshkevich , Sven Schnelle Subject: Re: perf test case 40 LLVM search and compile runs endless (eBPF linkage issue) Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org On Mon, May 23, 2022 at 12:52:06PM +0200, Thomas Richter wrote: > On s390 the test case 40 'LLVM search and compile' runs for ever: > > # date; timeout 30s perf test -F 40; date > Mon May 23 12:35:48 PM CEST 2022 > 40: LLVM search and compile : > 40.1: Basic BPF llvm compile : > Mon May 23 12:36:18 PM CEST 2022 > # > > Investigation by Ilya Leoshkevich revealed: > On s390 we hit an endless loop where bpf_object__next_program and bpf_program__next > infinitely call each other. We tracked this down to ld.so preferring the perf's > bpf_object__next_program weak copy over the libbpf's strong one. > > This is introduced with commit 2a4898fc264a ("perf tools: Add more weak libbpf functions") > > Also see discussion in > https://lore.kernel.org/lkml/YY%2FAR2Dcaws0BAE9@kernel.org/ > > How can this be fixed asap? Thanks a lot. I was just suggesting to remove that: https://lore.kernel.org/bpf/Yos8hq3NmBwemoJw@krava/T/#mda8abccbf475b99d25abe5498a5df1af2da82ee8 it's no longer needed and can cause problem apparently jirka