From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laine Stump Subject: Re: Regression in kernel 4.2.3+ (relative to 4.1.10) on AMD 990FX system with IOMMU enabled Date: Thu, 12 Nov 2015 12:33:53 -0500 Message-ID: <5644CD81.2020304@redhat.com> References: <563A3F64.50808@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <563A3F64.50808-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Cc: Joerg Roedel List-Id: iommu@lists.linux-foundation.org (Cc'ing Joerg because I have a question for him down towards the bottom...) On 11/04/2015 12:24 PM, Laine Stump wrote: > Last week I upgraded my Fedora 22 AMD 990FX system from kernel 4.1.10 to > 4.2.3 (standard Fedora builds) and multiple devices stopped working: > > * 00:14.2 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] SBx00 > Azalia (Intel HDA) (rev 40) > > * 02:00.[01] Ethernet controller: Intel Corporation 82576 Gigabit > Network Connection > > * 01:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Cedar > HDMI Audio [Radeon HD 5400/6300 Series] > > (The 1st is integrated on the motherboard, the 2nd & 3rd are behind an > AMD RD890 pci-pci bridge. There may be other devices failing, but these > are the ones immediately obvious.) > > Whatever is the source of the failure, it ends up that the drivers for > these devices aren't loaded. That is actually a bit misleading/incorrect - the igb device is apparently loaded for one of the two devices in the 82576 card (02:00.0), and one (out of expected 7) VF device entries is created in /sys/devices/pci0000:00/*, but something happens that results in none of these devices being put in /sys/class/net, the other 6 VFs don't get entries in /sys/device/pci0000:00/*, and the igb driver isn't loaded for the 2nd PF (02:00.1). > At Alex Williamson's suggestion, I tried disabling IOMMU in the BIOS, > and magically all the devices resumed normal operation (except that I > can't do vfio device assignment because the IOMMU is disabled). After a crash course in kernel building from Alex, I bisected down to commit aafd8ba - a kernel built without this commit succeeds in setting up all the devices mentioned, adding it causes failure (and a very long delay during boot). Joerg, do you have any ideas for debugging the problem further to see what in the commit causes this problem? (note that 2 other people with the same chipset but slightly different hardware plugged into it report no failure - see the other replies to the parent of this message for more detail). I'm happy to build a kernel with any suggested patches and report results... commit aafd8ba0ca74894b9397e412bbd7f8ea2662ead8 Author: Joerg Roedel Date: Thu May 28 18:41:39 2015 +0200 iommu/amd: Implement add_device and remove_device Implement these two iommu-ops call-backs to make use of the initialization and notifier features of the iommu core. Signed-off-by: Joerg Roedel