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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 6A4A2C6786F for ; Thu, 1 Nov 2018 11:43:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 265F8204FD for ; Thu, 1 Nov 2018 11:43:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 265F8204FD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.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 S1728424AbeKAUqM (ORCPT ); Thu, 1 Nov 2018 16:46:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:18554 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728012AbeKAUqM (ORCPT ); Thu, 1 Nov 2018 16:46:12 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 315F231256CB; Thu, 1 Nov 2018 11:43:36 +0000 (UTC) Received: from prarit.bos.redhat.com (prarit-guest.khw1.lab.eng.bos.redhat.com [10.16.200.63]) by smtp.corp.redhat.com (Postfix) with ESMTP id 90AB61054FBB; Thu, 1 Nov 2018 11:43:35 +0000 (UTC) Subject: Re: [PATCH AUTOSEL 4.19 022/146] cpupower: Fix coredump on VMWare To: Sasha Levin , stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Shuah Khan , Stafford Horne References: <20181031230541.28822-1-sashal@kernel.org> <20181031230541.28822-22-sashal@kernel.org> From: Prarit Bhargava Message-ID: <7c08983b-a8c5-0dbc-c8aa-2c6a6799e1ee@redhat.com> Date: Thu, 1 Nov 2018 07:43:35 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181031230541.28822-22-sashal@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Thu, 01 Nov 2018 11:43:36 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/31/2018 07:03 PM, Sasha Levin wrote: > From: Prarit Bhargava > > [ Upstream commit f69ffc5d3db8f1f03fd6d1df5930f9a1fbd787b6 ] > > cpupower crashes on VMWare guests. The guests have the AMD PStateDef MSR > (0xC0010064 + state number) set to zero. As a result fid and did are zero > and the crash occurs because of a divide by zero (cof = fid/did). This > can be prevented by checking the enable bit in the PStateDef MSR before > calculating cof. By doing this the value of pstate[i] remains zero and > the value can be tested before displaying the active Pstates. > > Check the enable bit in the PstateDef register for all supported families > and only print out enabled Pstates. > Hi Sasha, This patch, f69ffc5d3db8, depends on 8c22e2f69592 ("cpupower: Fix AMD Family 0x17 msr_pstate size"). Without 8c22e2f69592 the patch below will always read a value of "0" and not output the correct data. 8c22e2f69592 must be applied to any stable branch that f69ffc5d3db8 is applied to. P. > Signed-off-by: Prarit Bhargava > Cc: Shuah Khan > Cc: Stafford Horne > Signed-off-by: Shuah Khan (Samsung OSG) > Signed-off-by: Sasha Levin > --- > tools/power/cpupower/utils/cpufreq-info.c | 2 ++ > tools/power/cpupower/utils/helpers/amd.c | 5 +++++ > 2 files changed, 7 insertions(+) > > diff --git a/tools/power/cpupower/utils/cpufreq-info.c b/tools/power/cpupower/utils/cpufreq-info.c > index df43cd45d810..ccd08dd00996 100644 > --- a/tools/power/cpupower/utils/cpufreq-info.c > +++ b/tools/power/cpupower/utils/cpufreq-info.c > @@ -200,6 +200,8 @@ static int get_boost_mode(unsigned int cpu) > printf(_(" Boost States: %d\n"), b_states); > printf(_(" Total States: %d\n"), pstate_no); > for (i = 0; i < pstate_no; i++) { > + if (!pstates[i]) > + continue; > if (i < b_states) > printf(_(" Pstate-Pb%d: %luMHz (boost state)" > "\n"), i, pstates[i]); > diff --git a/tools/power/cpupower/utils/helpers/amd.c b/tools/power/cpupower/utils/helpers/amd.c > index bb41cdd0df6b..58d23997424d 100644 > --- a/tools/power/cpupower/utils/helpers/amd.c > +++ b/tools/power/cpupower/utils/helpers/amd.c > @@ -119,6 +119,11 @@ int decode_pstates(unsigned int cpu, unsigned int cpu_family, > } > if (read_msr(cpu, MSR_AMD_PSTATE + i, &pstate.val)) > return -1; > + if ((cpu_family == 0x17) && (!pstate.fam17h_bits.en)) > + continue; > + else if (!pstate.bits.en) > + continue; > + > pstates[i] = get_cof(cpu_family, pstate); > } > *no = i; >