Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758734AbeAIPNB (ORCPT + 1 other); Tue, 9 Jan 2018 10:13:01 -0500 Received: from bombadil.infradead.org ([65.50.211.133]:58738 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753379AbeAIPM7 (ORCPT ); Tue, 9 Jan 2018 10:12:59 -0500 Date: Tue, 9 Jan 2018 16:12:53 +0100 From: Peter Zijlstra To: Vince Weaver Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Ingo Molnar , Arnaldo Carvalho de Melo , Thomas Gleixner Subject: Re: perf: perf_fuzzer quickly locks up on 4.15-rc7 Message-ID: <20180109151253.GK6176@hirez.programming.kicks-ass.net> References: <20180108173005.lkglqrixb2ota6g2@gmail.com> <20180109102507.GG6176@hirez.programming.kicks-ass.net> <20180109132602.GA2369@hirez.programming.kicks-ass.net> 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 List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On Tue, Jan 09, 2018 at 08:44:23AM -0500, Vince Weaver wrote: > On Tue, 9 Jan 2018, Peter Zijlstra wrote: > > > So remind me again, how are you running that fuzzer? I'm running > > ./fast_repro99.sh as root. > > I'm running ./fast_repro98.sh on a regular haswell machine with paranoid > set to "0". > > I'll try your patch and see if it makes a difference. I suspect not, it shouldn't be PTI specific. > I can also try on a few other machines. I started setting up a fuzzing > cluster for this kind of thing but the multiport serial card I got for > logging the serial consoles crashes fairly quickly under load and I > haven't had time to track that down. So I don't think HSW has PT, which is something I cannot test on my IVB. OTOH HSW has PEBS real_ip, but that uses _less_ magic. In any case, I found yet another lockdep splat, trying to figure out wth to do about that. Will then continue running with fast_repro98.