From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759690Ab1LPB0P (ORCPT ); Thu, 15 Dec 2011 20:26:15 -0500 Received: from terminus.zytor.com ([198.137.202.10]:44749 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751084Ab1LPB0O (ORCPT ); Thu, 15 Dec 2011 20:26:14 -0500 Message-ID: <4EEA9E1E.9080308@zytor.com> Date: Thu, 15 Dec 2011 17:25:50 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:8.0) Gecko/20111115 Thunderbird/8.0 MIME-Version: 1.0 To: Jean Delvare CC: Andi Kleen , linux-kernel@vger.kernel.org, kay.sievers@vrfy.org, trenn@suse.de, Andi Kleen , davej@redhat.com, axboe@kernel.dk, herbert@gondor.hengli.com.au, ying.huang@intel.com, lenb@kernel.org Subject: Re: [PATCH 01/10] Add driver auto probing for x86 features References: <1323304882-27953-1-git-send-email-andi@firstfloor.org> <1323304882-27953-2-git-send-email-andi@firstfloor.org> <20111208103540.4778b896@endymion.delvare> <20111208144516.GE24062@one.firstfloor.org> <20111209211601.08dabc88@endymion.delvare> In-Reply-To: <20111209211601.08dabc88@endymion.delvare> X-Enigmail-Version: 1.3.4 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/09/2011 12:16 PM, Jean Delvare wrote: > > Irrelevant. You load a driver when any, not all, of the devices in the > system are supported by said driver. This obviously holds for PCI > devices and drivers (you don't refrain from loading the network card's > driver because that driver doesn't support your graphics card), the CPU > device case is no different (in theory at least.) > Well, it is, actually. We do a whole lot of tests using boot_cpu_has(), which really isn't about the boot CPU at all but rather is the intersection of all features supported by all the CPUs in the system. There are, however, a handful of drivers which want to be loaded for "any matching CPU" as opposed to "all matching CPUs" and I guess it would be useful to have that capability as an alternative. -hpa