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 7A718C004E4 for ; Wed, 13 Jun 2018 05:27:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2763920693 for ; Wed, 13 Jun 2018 05:27:19 +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="tCl+DLOq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2763920693 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 S934050AbeFMF1R (ORCPT ); Wed, 13 Jun 2018 01:27:17 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:49626 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754450AbeFMF1P (ORCPT ); Wed, 13 Jun 2018 01:27:15 -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=9df8WT0I+/msTiIuo0vVzuiBNF3mIduIYGEBWsiZmcA=; b=tCl+DLOqYB5R8OsU8+Shb2634 zr0YR72e4eG9xUD4lBNskqU75sYn1QQZmsX7Ra8X3cZ/NEck6ggBqBV8tdHbIlU7isVvCHYxCbWdO 6LlWx9uJu/xH1X+/OLWfj+xuOpqj5pN6jQdlLraiuV9/LpfmNlpymqFy2oSMJah7Czx8QH9/G8ecr 7wT2wJdI7yv9W8Avoih7QJNXc+CUb/rPdGpxvj2XQKKD2xe+IsBOOecSQH5/QRjzTaEWhstzIz1zY MnpTJPNPx37hPB7ipEeWbSprOHE2tQiBDdmfU7bQUP234IZbhbLOLCQjRLr/VjyYcUZK4DcTAwJ26 eTr3N6keQ==; Received: from static-50-53-52-16.bvtn.or.frontiernet.net ([50.53.52.16] helo=dragon.dunlab) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fSyJE-0005EW-AN; Wed, 13 Jun 2018 05:27:04 +0000 Subject: Re: [RFC PATCH 22/23] watchdog/hardlockup/hpet: Only enable the HPET watchdog via a boot parameter To: Ricardo Neri , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: 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> From: Randy Dunlap Message-ID: Date: Tue, 12 Jun 2018 22:26:57 -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: <1528851463-21140-23-git-send-email-ricardo.neri-calderon@linux.intel.com> 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 06/12/2018 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? > @@ -2587,6 +2587,9 @@ > please see 'nowatchdog'. > This is useful when you use a panic=... timeout and > need the box quickly up again. > + When hpet is specified, the NMI watchdog will be driven > + by an HPET timer, if available in the system. Otherwise, > + the perf-based implementation will be used. > > These settings can be accessed at runtime via > the nmi_watchdog and hardlockup_panic sysctls. thanks, -- ~Randy