From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932410Ab3BKU5J (ORCPT ); Mon, 11 Feb 2013 15:57:09 -0500 Received: from g6t0187.atlanta.hp.com ([15.193.32.64]:38900 "EHLO g6t0187.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932078Ab3BKU5H (ORCPT ); Mon, 11 Feb 2013 15:57:07 -0500 Message-ID: <1360616223.2950.15.camel@lorien2> Subject: Re: IO_PAGE_FAULTs on unity mapped regions during amd_iommu_init() in Linux 3.4 From: Shuah Khan Reply-To: shuah.khan@hp.com To: Greg KH Cc: Joerg Roedel , LKML , stable , iommu@lists.linux-foundation.org Date: Mon, 11 Feb 2013 13:57:03 -0700 In-Reply-To: <20130211194901.GA18115@kroah.com> References: <1359657210.6061.3.camel@lorien2> <20130201130035.GE25591@8bytes.org> <1359743519.2759.38.camel@lorien2> <20130205133104.GC2532@8bytes.org> <20130206121223.GT25591@8bytes.org> <1360204850.2615.10.camel@lorien2> <20130211194901.GA18115@kroah.com> Organization: ISS-Linux Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2013-02-11 at 11:49 -0800, Greg KH wrote: > On Wed, Feb 06, 2013 at 07:40:50PM -0700, Shuah Khan wrote: > > On Wed, 2013-02-06 at 13:12 +0100, Joerg Roedel wrote: > > > On Tue, Feb 05, 2013 at 06:57:21AM -0700, Shuah Khan wrote: > > > > Thanks much. I will hang on to this test system for testing your fix. > > > > > > Okay, here is the simple fix for v3.8-rc6. I guess it is not > > > straighforward to port it to v3.4, but it should be doable. > > > > > > From 2ecf57c85e67e0243b36b787d0490c0b47202ba8 Mon Sep 17 00:00:00 2001 > > > From: Joerg Roedel > > > Date: Wed, 6 Feb 2013 12:55:23 +0100 > > > Subject: [PATCH] iommu/amd: Initialize device table after dma_ops > > > > > > When dma_ops are initialized the unity mappings are > > > created. The init_device_table_dma() function makes sure DMA > > > from all devices is blocked by default. This opens a short > > > window in time where DMA to unity mapped regions is blocked > > > by the IOMMU. Make sure this does not happen by initializing > > > the device table after dma_ops. > > > > > > Signed-off-by: Joerg Roedel > > > > Joerg, > > > > I tested your patch on 3.8. I was able to reproduce the problem and then > > apply your patch to verify that the problem is fixed. This patch applies > > cleanly to 3.7.6, however I could not reproduce the problem on 3.7.6 > > without the patch. But the window exists on 3.7 as well. Your patch can > > be applied to 3.7.6 as is. > > > > I back-ported the patch to 3.4 and 3.0 and tested. I am sending those > > patches after this email. > > > > On 3.4.29 and 3.0.62 I was able to reproduce the problem and then > > applied the back-ported patch to verify that the problem is fixed. > > > > Thanks again for the fix. > > I'm lost here, why isn't this patch in Linus's tree already? You seem > to be sending backports for something that isn't there to backport yet. > > Please resend these patches to stable@vger.kernel.org, with the upstream > git commit id, when they are in Linus's tree, there's nothing I can do > with them for now, sorry. > > greg k-h I was hoping Joerg's patch would make it into Linus's tree by now. I tested the original patch and did the back-port to 3.4 and 3.0 at the same time, before I loose the test system. No worries. I will resend the patch when I have the commit id. Sorry for the confusion. Thanks, -- Shuah