From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753352Ab3BLGKr (ORCPT ); Tue, 12 Feb 2013 01:10:47 -0500 Received: from terminus.zytor.com ([198.137.202.10]:46429 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751267Ab3BLGKq (ORCPT ); Tue, 12 Feb 2013 01:10:46 -0500 Message-ID: <5119DCCD.70709@zytor.com> Date: Mon, 11 Feb 2013 22:10:21 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Ingo Molnar CC: Yinghai Lu , Thomas Gleixner , Ingo Molnar , Bjorn Helgaas , "Rafael J. Wysocki" , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 00/26] x86, irq: support ioapic device hotplug References: <1360351703-20571-1-git-send-email-yinghai@kernel.org> <20130211093417.GC23932@gmail.com> In-Reply-To: <20130211093417.GC23932@gmail.com> X-Enigmail-Version: 1.5 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/11/2013 01:34 AM, Ingo Molnar wrote: > > * Yinghai Lu wrote: > >> Hi, >> >> Current x86 code does not support iapic hotplug yet. > > Please give a better high-level description: outline how an > IO-APIC will be hotplugged physically and what changes the > user will experience. > > That needs at least 2 paragraphs, not one cursory sentence. Then > should come technical descriptions - but even those need > improvements, please first explain the current status quo, then > explain how that is inadequate for IO-APIC hot-plugging, *then* > only explain what you are doing in the patch ... > A few more notes: Please explain what you mean with pre-reserve IRQ blocks, and in particular, how do you know what to reserve and for what? Second, some of the things in this patchset seems to overlap with what we would need to support MSI (as opposed to MSI-X), and you have several patches related to MSI vs MSI-X. Are you also supporting multivector MSI (I believe the answer is no) or could some of this work make multivector MSI practical (possible)? -hpa