Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756837Ab2JRPCx (ORCPT ); Thu, 18 Oct 2012 11:02:53 -0400 Received: from terminus.zytor.com ([198.137.202.10]:45690 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753101Ab2JRPCv (ORCPT ); Thu, 18 Oct 2012 11:02:51 -0400 Message-ID: <50801A14.5010003@zytor.com> Date: Thu, 18 Oct 2012 08:02:44 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121009 Thunderbird/16.0 MIME-Version: 1.0 To: Konrad Rzeszutek Wilk CC: linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com, lenb@kernel.org, linux-acpi@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH 2/4] xen/lowlevel: Implement pvop call for load_idt (sidt). References: <1350481786-4969-1-git-send-email-konrad.wilk@oracle.com> <1350481786-4969-3-git-send-email-konrad.wilk@oracle.com> <507F4475.80705@zytor.com> <20121018144538.GA19782@localhost.localdomain> In-Reply-To: <20121018144538.GA19782@localhost.localdomain> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 923 Lines: 25 On 10/18/2012 07:45 AM, Konrad Rzeszutek Wilk wrote: >> >> OK... this seems like another excellent set of pvops calls that >> should be nukable to Kingdom Come. There is no reason, ever, to >> read the IDT and GDT from the kernel... the kernel already knows >> what they should be! > > Even during suspend and resume cycle? There are the sequence of > sidt/lidt calls being done there. And we do need to filter at > least the sidt call - and in the case of ACPI suspend path, > the lidt. Yes, I am pretty sure we can make static guarantees on the IDT and GDTs. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- 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/