Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760421Ab0HFGwS (ORCPT ); Fri, 6 Aug 2010 02:52:18 -0400 Received: from tx2ehsobe003.messaging.microsoft.com ([65.55.88.13]:2831 "EHLO TX2EHSOBE005.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753848Ab0HFGwN (ORCPT ); Fri, 6 Aug 2010 02:52:13 -0400 X-SpamScore: -16 X-BigFish: VPS-16(zz1432N98dN936eMzz1202hzzz32i2a8h43h61h) X-Spam-TCS-SCL: 0:0 X-WSS-ID: 0L6PXQQ-02-9UL-02 X-M-MSG: Date: Fri, 6 Aug 2010 08:52:03 +0200 From: Robert Richter To: Cyrill Gorcunov CC: Don Zickus , Peter Zijlstra , Lin Ming , Ingo Molnar , "fweisbec@gmail.com" , "linux-kernel@vger.kernel.org" , "Huang, Ying" , Yinghai Lu , Andi Kleen Subject: Re: A question of perf NMI handler Message-ID: <20100806065203.GR26154@erda.amd.com> References: <1280931093.1923.1194.camel@laptop> <20100804145203.GP3353@redhat.com> <1280934161.1923.1294.camel@laptop> <20100804151858.GB5130@lenovo> <20100804155002.GS3353@redhat.com> <20100804161046.GC5130@lenovo> <20100804162026.GU3353@redhat.com> <20100804163930.GE5130@lenovo> <20100804184806.GL26154@erda.amd.com> <20100804192634.GG5130@lenovo> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20100804192634.GG5130@lenovo> User-Agent: Mutt/1.5.20 (2009-06-14) X-Reverse-DNS: unknown Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1318 Lines: 32 On 04.08.10 15:26:34, Cyrill Gorcunov wrote: > yes, that is what I meant by nmi_sc register. I think we need to restucturize > current default_do_nmi handler but how to be with perfs I don't know at moment > if perf register gets overflowed (ie already has pedning nmi) but we handle > it in early nmi cycle this would lead to strange results. Need to think. > > > > > So you can decide to either get an unrecovered nmi panic triggered by > > a perfctr or losing unknown nmis from other sources. Maybe this can be > > fixed by implementing handlers for those sources. I was playing around with it yesterday trying to fix this. My idea is to skip an unkown nmi if the privious nmi was a *handled* perfctr nmi. I will probably post an rfc patch early next week. Another problem I encountered is that unknown nmis from the chipset are not reenabled, thus when hitting the nmi button I only see one unknown nmi message per boot, if I reenable it, I get an nmi storm firing nmi_watchdog. Uhh.... -Robert -- Advanced Micro Devices, Inc. Operating System Research Center -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/