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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 E6A4FC4360F for ; Wed, 3 Apr 2019 19:19:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3A7F20882 for ; Wed, 3 Apr 2019 19:19:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="FVkLBpL+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726510AbfDCTTs (ORCPT ); Wed, 3 Apr 2019 15:19:48 -0400 Received: from mail-lj1-f196.google.com ([209.85.208.196]:35096 "EHLO mail-lj1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726206AbfDCTTs (ORCPT ); Wed, 3 Apr 2019 15:19:48 -0400 Received: by mail-lj1-f196.google.com with SMTP id t4so15930190ljc.2 for ; Wed, 03 Apr 2019 12:19:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=1RxFl1rlgcdvv54vamWlsrxDybk3dbBPoWolgwn8RJ4=; b=FVkLBpL+815Qo+W0sM39wLykAtzXvimgcpO/3l8jev5VlqeRZhd/GXw9oQPOHKjQBo sUqqZTjNabyBJsMQxBhqdz2DFjnRRnNxYVFhZHWFlO31V8FhFtOfwhSV3wHeYcya0n0t BCcVWMwxZtFYdmq+oVjsyveFtr0Kis04hPcg/RsqK+psY/8+sBJoFmu1nwUqRQxqg9W0 S7uWcVfizfkb9yKvy9qY1BopKlj/iv6iIyquKLAa1/2e0wsNBDwWFNZ05qzPjGmh6/9t H/tDYkhS2ZiXA+mPwM0YC+Ck4wE8TgBmAH4f6xMBVj5/xnPGAFR1L2MjUBXzLWR7HFAC IfJA== 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:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=1RxFl1rlgcdvv54vamWlsrxDybk3dbBPoWolgwn8RJ4=; b=ba+v9OtoUsNhN7v/dYlCSHstWVY+h26sm3lA0tM3ZkaTAlGWuqmvt9RDK/JC3G1I2m KqC1G9T2tJKG41SQBs0cVLd3UtN2kFUv9Nftacg8qw0XnwGKfLVmukKzNqZ2fUqngGk/ 6meYSjbMfwCN3bFL9a6N/yKI1oorX+cTerrISc7tqLR5td2vkI+BS3kYnvBJlyLUn4jR R6kaJM985uzFwypWwyxJN7dTRsulmHOYdOiyoXZPpqCr/ayekfjV7xmCtBphOxWg0VUQ TQnOG3bvPErQsCMmJ8G547I4ce/KOyHPjVOmnJcm/IrD0VS8EOATa0vs7AIDhXIUNCPP uuxA== X-Gm-Message-State: APjAAAX+IpxaAtz2HOnRV6FLCXUCBs2ofWeSKJYrrQny6E7wjxvh6EPg NhY+g87rQXy0njPhFRJS+W8= X-Google-Smtp-Source: APXvYqxfsO2kVtsCrdBu9U8Be9Jz4KpB+I3UF34SmpHt31t8efJdLZvURbQKSOYj9JgVQs5AtSut1Q== X-Received: by 2002:a2e:895a:: with SMTP id b26mr802114ljk.89.1554319186144; Wed, 03 Apr 2019 12:19:46 -0700 (PDT) Received: from uranus.localdomain ([5.18.103.226]) by smtp.gmail.com with ESMTPSA id z8sm3472677ljc.50.2019.04.03.12.19.44 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 03 Apr 2019 12:19:45 -0700 (PDT) Received: by uranus.localdomain (Postfix, from userid 1000) id ADD4F46041D; Wed, 3 Apr 2019 22:19:44 +0300 (MSK) Date: Wed, 3 Apr 2019 22:19:44 +0300 From: Cyrill Gorcunov To: Vince Weaver Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, Arnaldo Carvalho de Melo , Alexander Shishkin , Ingo Molnar , Borislav Petkov , Namhyung Kim , Thomas Gleixner , Jiri Olsa , Stephane Eranian Subject: Re: perf: perf_fuzzer crashes on Pentium 4 systems Message-ID: <20190403191944.GH1421@uranus.lan> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 03, 2019 at 10:59:32AM -0400, Vince Weaver wrote: > > so moving this to its own thread. > > There was a two-part question asked. > 1. Can the perf-fuzzer crash a Pentium 4 system > 2. Does anyone care anymore? > > The answer to #1 turns out to be "yes" > I'm not sure about #2 (but it's telling my p4 test system hadn't been > turned on in over 3 years). > > In any case the perf_fuzzer can crash my p4 system within an hour or so. > The debugging from this isn't great, I forget what the preferred debug > things to enable in the kernel hacking menu are. > > Here is one crash that just happened: > > The instruction at RIP is unhelpfully > ./arch/x86/include/asm/processor.h:400 > which is > DECLARE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union) __visible; > > Though looking at the assembly it looks like > p4_pmu_enable_event() is called with NULL as the paramater. > You know, seems I got what happened -- p4_general_events do not cover all general events, they stop at PERF_COUNT_HW_BUS_CYCLES, while more 3 general event left. This is 'cause I've not been following pmu evolution in code. I will try to cover this events hopefully more less soon and send you a patch to test (if you don't mind).