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=-0.6 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,T_DKIM_INVALID autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by aws-us-west-2-korg-lkml-1.web.codeaurora.org (Postfix) with ESMTP id 40EC0C07D5C for ; Thu, 14 Jun 2018 03:30:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DD9E820864 for ; Thu, 14 Jun 2018 03:30:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="C0evJZFw" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DD9E820864 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org 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 S935976AbeFNDaa (ORCPT ); Wed, 13 Jun 2018 23:30:30 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:60560 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935858AbeFNDa2 (ORCPT ); Wed, 13 Jun 2018 23:30:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To: Subject:Sender:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=b6WsKdtUOFnJJrfLbdKH/eKLJ5e+r5+ABHAtJmdcA0I=; b=C0evJZFwUEuJ+RylN/9XkzcnF sxA/Uml++JThVkYdhYH4/GTVALMDeCu2th+sqdQ3bLMiUylTRSaMYXfQORuyQ9RHSUur58en3mrHR qXiAa/Mb4oVIXZQlnOZnonJgTfFmvKNOnkqypXvTe+IeWZ9/oI6ZW8IkK+PEDVJMCbAec5TrIME+h o94hMfE2yp2FX5GRdHq+yThB8/egW4TVjdo3LRaKYKSlFRXQzqlRxoX7e7R0U3KvA9cJJvjuIpFuT G8IB3/TWfZGpXrqXOOgCazoLq+sqifoxUhDyYGJR6o44SmWg4G0DCH507EUTJxN1WZB5rajOsMaXE XqlpPPjJw==; Received: from static-50-53-52-16.bvtn.or.frontiernet.net ([50.53.52.16] helo=midway.dunlab) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fTIxY-0000bv-DV; Thu, 14 Jun 2018 03:30:04 +0000 Subject: Re: [RFC PATCH 22/23] watchdog/hardlockup/hpet: Only enable the HPET watchdog via a boot parameter To: Ricardo Neri Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Andi Kleen , Ashok Raj , Borislav Petkov , Tony Luck , "Ravi V. Shankar" , x86@kernel.org, sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Jacob Pan , "Rafael J. Wysocki" , Don Zickus , Nicholas Piggin , Michael Ellerman , Frederic Weisbecker , Alexei Starovoitov , Babu Moger , Mathieu Desnoyers , Masami Hiramatsu , Peter Zijlstra , Andrew Morton , Philippe Ombredanne , Colin Ian King , Byungchul Park , "Paul E. McKenney" , "Luis R. Rodriguez" , Waiman Long , Josh Poimboeuf , Davidlohr Bueso , Christoffer Dall , Marc Zyngier , Kai-Heng Feng , Konrad Rzeszutek Wilk , David Rientjes , iommu@lists.linux-foundation.org References: <1528851463-21140-1-git-send-email-ricardo.neri-calderon@linux.intel.com> <1528851463-21140-23-git-send-email-ricardo.neri-calderon@linux.intel.com> <20180614005839.GA22358@voyager> From: Randy Dunlap Message-ID: <2cde62b1-5218-0169-4f9d-1139f83a25c1@infradead.org> Date: Wed, 13 Jun 2018 20:30:00 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180614005839.GA22358@voyager> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/13/2018 05:58 PM, Ricardo Neri wrote: > On Tue, Jun 12, 2018 at 10:26:57PM -0700, Randy Dunlap wrote: >> On 06/12/2018 05:57 PM, Ricardo Neri wrote: >>> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt >>> index f2040d4..a8833c7 100644 >>> --- a/Documentation/admin-guide/kernel-parameters.txt >>> +++ b/Documentation/admin-guide/kernel-parameters.txt >>> @@ -2577,7 +2577,7 @@ >>> Format: [state][,regs][,debounce][,die] >>> >>> nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels >>> - Format: [panic,][nopanic,][num] >>> + Format: [panic,][nopanic,][num,][hpet] >>> Valid num: 0 or 1 >>> 0 - turn hardlockup detector in nmi_watchdog off >>> 1 - turn hardlockup detector in nmi_watchdog on >> >> This says that I can use "nmi_watchdog=hpet" without using 0 or 1. >> Is that correct? > > Yes, this what I meant. In my view, if you set nmi_watchdog=hpet it > implies that you want to activate the NMI watchdog. In this case, perf. > > I can see how this will be ambiguous for the case of perf and arch NMI > watchdogs. > > Alternative, a new parameter could be added; such as nmi_watchdog_type. I > didn't want to add it in this patchset as I think that a single parameter > can handle the enablement and type of the NMI watchdog. > > What do you think? I think it's OK like it is. thanks, -- ~Randy