Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751378AbdCNPmn (ORCPT ); Tue, 14 Mar 2017 11:42:43 -0400 Received: from mga11.intel.com ([192.55.52.93]:19828 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751108AbdCNPmO (ORCPT ); Tue, 14 Mar 2017 11:42:14 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,164,1486454400"; d="scan'208";a="235979385" Date: Tue, 14 Mar 2017 08:41:55 -0700 From: Andi Kleen To: Thomas Gleixner Cc: Andi Kleen , bhelgaas@google.com, x86@kernel.org, linux-pci@vger.kernel.org, eranian@google.com, Peter Zijlstra , LKML Subject: Re: [PATCH 3/4] x86, pci: Add interface to force mmconfig Message-ID: <20170314154155.GG32070@tassilo.jf.intel.com> References: <20170302232104.10136-1-andi@firstfloor.org> <20170302232104.10136-3-andi@firstfloor.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 502 Lines: 13 > And the way how this function is used is a horrible hack. It's called from > a random driver at some random point in time. > > The proper solution is to identify the bus at the point where the bus is > discovered and switch it to mmconfig if possible. But how would you know that it is safe? AFAIK the only one who knows "this is an internal SOC device" is the driver. Or are you saying it should be enabled unconditionally for everything? Or define some quirk table just for this purpose? -Andi