From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [PATCH 2/4] xen/lowlevel: Implement pvop call for load_idt (sidt). Date: Thu, 18 Oct 2012 08:02:44 -0700 Message-ID: <50801A14.5010003@zytor.com> 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> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: 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 In-Reply-To: <20121018144538.GA19782@localhost.localdomain> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org 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 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.