From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752081AbdJCOWH (ORCPT ); Tue, 3 Oct 2017 10:22:07 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:49538 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751156AbdJCOWF (ORCPT ); Tue, 3 Oct 2017 10:22:05 -0400 Date: Tue, 3 Oct 2017 15:22:05 +0100 From: Will Deacon To: Kim Phillips Cc: Arnaldo Carvalho de Melo , linux-arm-kernel@lists.infradead.org, marc.zyngier@arm.com, mark.rutland@arm.com, tglx@linutronix.de, peterz@infradead.org, alexander.shishkin@linux.intel.com, robh@kernel.org, suzuki.poulose@arm.com, pawel.moll@arm.com, mathieu.poirier@linaro.org, mingo@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 6/7] drivers/perf: Add support for ARMv8.2 Statistical Profiling Extension Message-ID: <20171003142205.GD26552@arm.com> References: <1506607791-8621-1-git-send-email-will.deacon@arm.com> <1506607791-8621-7-git-send-email-will.deacon@arm.com> <20170929171940.2aa33d00463b1e9c987aea15@arm.com> <20171002141405.GC12847@arm.com> <20171002164930.GB2121@redhat.com> <20171002183524.ab23b255b6d03331bb36f75a@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171002183524.ab23b255b6d03331bb36f75a@arm.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 02, 2017 at 06:35:24PM -0500, Kim Phillips wrote: [trim other stuff] > Meanwhile, when I build this v5 arm_spe_pmu as a module, load it, do a > perf list, rmmod it, then re-load it, I get an Oops: > > # insmod arm_spe_pmu.ko > [ 2018.623646] arm_spe_pmu spe-pmu@0: probed for CPUs 0-3 [max_record_sz 64, align 1, features 0xf] > [ 2018.626346] arm_spe_pmu spe-pmu@1: probed for CPUs 4-7 [max_record_sz 64, align 1, features 0xf] > # ./perf list > [ 2021.649688] Unable to handle kernel NULL pointer dereference at virtual address 00000038 [...] Cheers for the report. Fix here: https://lkml.org/lkml/2017/10/3/564 Will