From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:15194 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754610Ab2IUR6K (ORCPT ); Fri, 21 Sep 2012 13:58:10 -0400 Message-ID: <505CAAA1.3040409@redhat.com> Date: Fri, 21 Sep 2012 13:57:53 -0400 From: Don Dutile MIME-Version: 1.0 To: Konrad Rzeszutek Wilk CC: Takao Indoh , vgoyal@redhat.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, bhelgaas@google.com, hbabu@us.ibm.com, ishii.hironobu@jp.fujitsu.com, martin.wilck@ts.fujitsu.com Subject: Re: [RFC][PATCH] Reset PCIe devices to address DMA problem on kdump with iommu References: <501BB4EF.7080909@jp.fujitsu.com> <20120803114643.GA28330@redhat.com> <501F4877.5050605@jp.fujitsu.com> <20120806203902.GH25559@redhat.com> <50473306.1070803@jp.fujitsu.com> <20120910143604.GB639@redhat.com> <504F1343.7030607@jp.fujitsu.com> <20120914200334.GA9041@phenom.dumpdata.com> In-Reply-To: <20120914200334.GA9041@phenom.dumpdata.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-pci-owner@vger.kernel.org List-ID: On 09/14/2012 04:03 PM, Konrad Rzeszutek Wilk wrote: >> As to the boot parameter to enable this function, you suggested using >> reset_devices. I found that on a certain platform resetting devices >> caused PCIe error due to a hardware bug. Therefore I think we need >> new parameter apart from reset_devices to disable this function on >> such a machine. > > Wouldn't a DMI quirk be better for this? That way the second kernel > internally would know not to do this. > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html a DMI quirk for a PCIe switch? pci-quirk maybe? there is a hook in per-device pci reset code path, which could be setup for such a case.