From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932782AbXCGFTi (ORCPT ); Wed, 7 Mar 2007 00:19:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964865AbXCGFTi (ORCPT ); Wed, 7 Mar 2007 00:19:38 -0500 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:34201 "EHLO ebiederm.dsl.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932782AbXCGFTh (ORCPT ); Wed, 7 Mar 2007 00:19:37 -0500 From: ebiederm@xmission.com (Eric W. Biederman) To: michael@ellerman.id.au Cc: Linus Torvalds , linux-kernel@vger.kernel.org, linux-pci@atrey.karlin.mff.cuni.cz, Greg Kroah-Hartman Subject: Re: [PATCH 2/3] msi: Fixup the msi enable/disable logic References: <1172802408.518.44.camel@concordia.ozlabs.ibm.com> Date: Tue, 06 Mar 2007 22:19:06 -0700 In-Reply-To: <1172802408.518.44.camel@concordia.ozlabs.ibm.com> (Michael Ellerman's message of "Fri, 02 Mar 2007 11:26:48 +0900") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Michael Ellerman writes: > > Hi Eric, comments below .. > > > I get the reasoning for disabling MSI before we start writing back the > config space, but don't we want to re-enable MSI on the way out? We are restoring the entire msi flags register which includes the enable bit, setting it a second time is gratuitous. In addition if we are restoring the register when the enable bit is not set. (because we don't have a mask bit) enabling the msi state is actually the wrong thing to do. But I admit that case can only happen after the additions in my last patch. Eric