Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751900AbXBPK1e (ORCPT ); Fri, 16 Feb 2007 05:27:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751901AbXBPK1e (ORCPT ); Fri, 16 Feb 2007 05:27:34 -0500 Received: from 207.47.60.150.static.nextweb.net ([207.47.60.150]:17935 "EHLO webmail.xensource.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751900AbXBPK1d convert rfc822-to-8bit (ORCPT ); Fri, 16 Feb 2007 05:27:33 -0500 X-Greylist: delayed 1490 seconds by postgrey-1.27 at vger.kernel.org; Fri, 16 Feb 2007 05:27:33 EST X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Subject: RE: [patch 14/21] Xen-paravirt: Add XEN config options and disableunsupported config options. Date: Fri, 16 Feb 2007 02:00:39 -0800 Message-ID: X-MS-Has-Attach: X-MS-TNEF-Correlator: thread-topic: [patch 14/21] Xen-paravirt: Add XEN config options and disableunsupported config options. Thread-Index: AcdRnIFegKnbAY+pRYux0pTDKlRLwQAFFnNg From: "Christian Limpach" To: "Jeremy Fitzhardinge" , "Andrew Morton" Cc: "Chris Wright" , "Andi Kleen" , "Keir Fraser" , , "Ian Pratt" , , "Steven Hand" , Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1110 Lines: 35 Jeremy Fitzhardinge wrote: > Andrew Morton wrote: > > On Thu, 15 Feb 2007 22:14:45 -0800 Dan Hecht > wrote: > > > > > >>> config PREEMPT > >>> bool "Preemptible Kernel (Low-Latency Desktop)" > >>> + depends on !XEN > >>> help > >>> This option reduces the latency of the kernel by making > >>> all kernel code (that is not executing in a critical section) > >>> > >>> > > > > Oh, so that's why it doesn't break when CONFIG_PREEMPT=y. > In which case > > that preempt_disable() I spotted is wrong-and-unneeded. > > > > Why doesn't Xen work with preemption?? > > > > I've forgotten the details. Ian? Keir? Steven? Maybe it > can be done. With CONFIG_PREEMPT, we can have preempted threads reference machine addresses across save/restore. After restore, these machine addresses will be incorrect. Christian - 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/