Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423189AbXBUWRP (ORCPT ); Wed, 21 Feb 2007 17:17:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1423190AbXBUWRP (ORCPT ); Wed, 21 Feb 2007 17:17:15 -0500 Received: from mta2.cl.cam.ac.uk ([128.232.0.14]:42534 "EHLO mta2.cl.cam.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1423189AbXBUWRN (ORCPT ); Wed, 21 Feb 2007 17:17:13 -0500 User-Agent: Microsoft-Entourage/11.3.3.061214 Date: Wed, 21 Feb 2007 22:16:15 +0000 Subject: Re: [patch 17/24] Xen-paravirt_ops: avoid having a bad selector in %gs during context switch From: Keir Fraser To: Andi Kleen , CC: Chris Wright , , Andrew Morton , Message-ID: Thread-Topic: [patch 17/24] Xen-paravirt_ops: avoid having a bad selector in %gs during context switch Thread-Index: AcdWBebHJZ96rMH5EduN6gAWy6hiGQ== In-Reply-To: <200702212310.02218.ak@suse.de> 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: 863 Lines: 24 On 21/2/07 22:10, "Andi Kleen" wrote: >> /* >> + * Temporary hack: zero gs now that we've saved it so that Xen >> + * doesn't try to reload the old value after changing the GDT >> + * during the context switch. This can go away once Xen has >> + * been taught to only reload %gs when it absolutely must. >> + */ >> + loadsegment(gs, 0); > > Sorry, but i don't really want that unconditionally in the context switch. > Adding a paravirt ops for it would be also ugly. Can Xen be fixed? This is not an issue for correctness so this can safely be removed and still work with current Xen. -- Keir - 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/