From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756619Ab2B2WdT (ORCPT ); Wed, 29 Feb 2012 17:33:19 -0500 Received: from oproxy4-pub.bluehost.com ([69.89.21.11]:33384 "HELO oproxy4-pub.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1756541Ab2B2WdR (ORCPT ); Wed, 29 Feb 2012 17:33:17 -0500 Message-ID: <4F4EA7B1.9060607@xenotime.net> Date: Wed, 29 Feb 2012 14:33:21 -0800 From: Randy Dunlap User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.15) Gecko/20110323 Thunderbird/3.1.9 MIME-Version: 1.0 To: "Rafael J. Wysocki" CC: Jesse Barnes , LKML , linux-pci@vger.kernel.org Subject: Re: [PATCH] PCI / PCIe: Introduce command line option to disable ARI References: <201202292309.42051.rjw@sisk.pl> In-Reply-To: <201202292309.42051.rjw@sisk.pl> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Identified-User: {1807:box742.bluehost.com:xenotime:xenotime.net} {sentby:smtp auth 50.53.38.135 authed with rdunlap@xenotime.net} Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/29/2012 02:09 PM, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > > There are PCIe devices on the market that report ARI support but > then fail to initialize correctly when ARI is actually used. This > leads to situations in which kernels 2.6.34 and newer fail to handle > systems where the previous kernels worked without any apparent > problems. Unfortunately, it is currently unknown how many such > devices are there. > > For this reason, introduce a new kernel command line option, > pci=noari, allowing users to disable PCIe ARI altogether if they > see problems with PCIe device initialization. > > Signed-off-by: Rafael J. Wysocki > --- > drivers/pci/pci.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > Index: linux/drivers/pci/pci.c > =================================================================== > --- linux.orig/drivers/pci/pci.c > +++ linux/drivers/pci/pci.c > @@ -94,6 +94,9 @@ u8 pci_cache_line_size; > */ > unsigned int pcibios_max_latency = 255; > > +/* If set, the PCIe ARI capability will not be used. */ > +static bool pcie_ari_disabled; Please update Documentation/kernel-parameters.txt . -- ~Randy