Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161383AbWKOU0S (ORCPT ); Wed, 15 Nov 2006 15:26:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030975AbWKOU0S (ORCPT ); Wed, 15 Nov 2006 15:26:18 -0500 Received: from smtp.osdl.org ([65.172.181.4]:2781 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1030952AbWKOU0R (ORCPT ); Wed, 15 Nov 2006 15:26:17 -0500 Date: Wed, 15 Nov 2006 12:21:18 -0800 From: Andrew Morton To: Andi Kleen Cc: Linus Torvalds , discuss@x86-64.org, William Cohen , Eric Dumazet , Komuro , Ernst Herzberg , Andre Noll , oprofile-list@lists.sourceforge.net, Jens Axboe , linux-usb-devel@lists.sourceforge.net, phil.el@wanadoo.fr, Adrian Bunk , Ingo Molnar , Alan Stern , linux-pci@atrey.karlin.mff.cuni.cz, Stephen Hemminger , Prakash Punnoor , Len Brown , Alex Romosan , gregkh@suse.de, Linux Kernel Mailing List , "Eric W. Biederman" , Andrey Borzenkov Subject: Re: [discuss] Re: 2.6.19-rc5: known regressions (v3) Message-Id: <20061115122118.14fa2177.akpm@osdl.org> In-Reply-To: <200611152023.53960.ak@suse.de> References: <200611151945.31535.ak@suse.de> <200611152023.53960.ak@suse.de> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.6; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1568 Lines: 46 On Wed, 15 Nov 2006 20:23:53 +0100 Andi Kleen wrote: > > > The fact is, it used to work, and the kernel changed interfaces, so now it > > doesn't. > > No, it didn't work. oprofile may have done something, but it > just silently killed the NMI watchdog in the process. > That was never acceptable. But people could get profiles out. I know, I've seen them! > Now we do proper accounting of NMI sources and also proper allocation > of performance counters. > > > > Yes, "oprofile" should be fixed to not depend on that, but the kernel > > shouldn't change the interfaces, and we should add back the zero entry. > > That would break the nmi watchdog again. > > Anyways, there is a sysctl to disable the nmi watchdog if someone > is desperate. > > But I think it is clearly oprofile who did wrong here and needs > to be fixed. > Is it correct to say that oprofile-on-2.6.18 works, and that oprofile-on-2.6.19-rc5 does not? Or is there some sort of workaround for this, or does 2.6.19-rc5 only fail in some particular scenarios? If it's really true that oprofile is simply busted then that's a serious problem and we should find some way of unbusting it. If that means just adding a dummy "0" entry which always returns zero or something like that, then fine. But we can't just go and bust it. - 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/