Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423415AbXBHV0e (ORCPT ); Thu, 8 Feb 2007 16:26:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1423416AbXBHV0e (ORCPT ); Thu, 8 Feb 2007 16:26:34 -0500 Received: from smtp-outbound-1.vmware.com ([65.113.40.141]:50252 "EHLO smtp-outbound-1.vmware.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1423415AbXBHV0d (ORCPT ); Thu, 8 Feb 2007 16:26:33 -0500 Message-ID: <45CB9588.50300@vmware.com> Date: Thu, 08 Feb 2007 13:26:32 -0800 From: Zachary Amsden User-Agent: Thunderbird 1.5.0.9 (X11/20061206) MIME-Version: 1.0 To: Dmitry Torokhov CC: Rusty Russell , Pavel Machek , Andi Kleen , Linux Kernel Mailing List , Andrew Morton , Jeremy Fitzhardinge , Chris Wright Subject: Re: [PATCH 9/11] Panic delay fix References: <200702060353.l163rUmj000771@zach-dev.vmware.com> <20070206122729.GC47229@muc.de> <45C8FA2D.6010706@vmware.com> <20070207123552.GD4481@ucw.cz> <1170880572.11736.4.camel@localhost.localdomain> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1069 Lines: 26 Dmitry Torokhov wrote: > > However I am not really fond of idea of adding constructs like this > all over the code: > > #define USE_REAL_TIME_DELAY_I_REALLY_MEAN_IT_THIS_TIME_I_SWEAR > > as the time passes... Drivers should be blissfully ignorant of being > run on virtual hardware. I agree in general, but there are two uses for this ugly construct. One is for drivers and isolated sections of code which actually interact with the real world. They need real time delays. The only two examples so far are SMP coprocessor bootstrapping and blinking LEDs with a recognizable frequency. I don't expect many more to show up. The other use for this construct is compiling a hardware privileged virtual domain that actually drives real hardware - you can just define this globally to override any delay masking. Zach - 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/