From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V4mTp-0007OX-KZ for kexec@lists.infradead.org; Thu, 01 Aug 2013 06:35:23 +0000 Received: from m4.gw.fujitsu.co.jp (unknown [10.0.50.74]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id A395E3EE0B6 for ; Thu, 1 Aug 2013 15:34:45 +0900 (JST) Received: from smail (m4 [127.0.0.1]) by outgoing.m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 91DEB45DE52 for ; Thu, 1 Aug 2013 15:34:45 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (s4.gw.fujitsu.co.jp [10.0.50.94]) by m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 7860245DE4E for ; Thu, 1 Aug 2013 15:34:45 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 677331DB803F for ; Thu, 1 Aug 2013 15:34:45 +0900 (JST) Received: from m1001.s.css.fujitsu.com (m1001.s.css.fujitsu.com [10.240.81.139]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 191BF1DB802F for ; Thu, 1 Aug 2013 15:34:45 +0900 (JST) Message-ID: <51FA015E.10901@jp.fujitsu.com> Date: Thu, 01 Aug 2013 15:34:06 +0900 From: Takao Indoh MIME-Version: 1.0 Subject: Re: [PATCH v2] PCI: Reset PCIe devices to stop ongoing DMA References: <1368509365-2260-1-git-send-email-indou.takao@jp.fujitsu.com> <51F85BCC.2070103@jp.fujitsu.com> <1699397.FXoFYIGzbk@vostro.rjw.lan> In-Reply-To: <1699397.FXoFYIGzbk@vostro.rjw.lan> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=twosheds.infradead.org@lists.infradead.org To: bhelgaas@google.com Cc: alex.williamson@redhat.com, linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, rjw@sisk.pl, hbabu@us.ibm.com, iommu@lists.linux-foundation.org, ddutile@redhat.com, bill.sumner@hp.com, ishii.hironobu@jp.fujitsu.com, vgoyal@redhat.com (2013/08/01 6:23), Rafael J. Wysocki wrote: > On Wednesday, July 31, 2013 03:08:03 PM Bjorn Helgaas wrote: >> [+cc Rafael, linux-acpi] >> >> On Tue, Jul 30, 2013 at 6:35 PM, Takao Indoh wrote: >> >>> On x86, currently IOMMU initialization run *after* PCI enumeration, but >>> what you are talking about is that it should be changed so that x86 >>> IOMMU initialization is done *before* PCI enumeration like sparc, right? >> >> Yes. I don't know whether or when that initialization order will ever >> be changed, but I do think we should avoid building more >> infrastructure that depends on the current order. >> >> Changing the order is a pretty big deal because it's a lot more than >> just the IOMMU. Basically I think we should be enumerating ACPI >> devices, including the IOMMU, before PCI devices, but there's a lot of >> legacy involved in that area. Added Rafael in case he has any >> thoughts. > > Well, actually, I'm not really familiar with IOMMUs, sorry. > > I do think that initializing IOMMU before PCI enumeration would be better, > however. At least if the ordering should be the same on all architectures, > which I suppose is the case, that's the one I'd choose. Ok guys. If x86 IOMMU maintainer also thinks changing order is necessary, maybe I need to give up device reset in kdump kernel and consider doing it in panic kernel. Either way, I need bus reset interface to reset devices. Bjorn, could you review the bus reset patches Alex posted yesterday? Thanks, Takao Indoh _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec