Ubuntu 17.04 with 4.10.0-21, libvirt 2.5.0, QEMU 2.8, and virt-manager 1.3.2.
Gigabyte EX58-UD3R Rev 1.6, ICH10 (00:1b.0) audio, x5675 (Westmere).
Nvidia GTX 275 for the host, GTX 1050 Ti for the VM.
Added to /etc/default/grub, updated grub, rebooted, and replaced the previous
entry each time:
intel_iommu=igfx_off (Audio works, breaks IOMMU)
intel_iommu=on,igfx_off (Breaks audio)
intel_iommu=on,igfx_off snd_hda_intel.align_buffer_size=1 (Breaks audio)
intel_iommu=on iommu=pt (Breaks audio)
dmesg gives with intel_iommu=on:
DMAR: [DMA Read] Request device [00:1b.0] fault addr b000 [fault reason 02]
Present bit in context entry is clear
THE FIX:
Alex Williamson created a patch that was verified by Matthieu Speder
https://bugzilla.kernel.org/show_bug.cgi?id=76331
https://patchwork.kernel.org/patch/4505951/
** Bug watch added: Linux Kernel Bug Tracker #76331
https://bugzilla.kernel.org/show_bug.cgi?id=76331
--
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to alsa-driver in Ubuntu.
https://bugs.launchpad.net/bugs/1428121
Title:
Intel HDMI Audio not working with IOMMU enabled
Status in ALSA driver:
Unknown
Status in alsa-driver package in Ubuntu:
Confirmed
Bug description:
New ASRock Z97 Extreme 6 motherboard with an Intel i7 4790S and an
Nvidia GTX 650.
Host uses Intel IGD for video and HDMI audio out.
When I pass kernel flags 'intel_iommu=on' or 'intel_iommu=on,igfx_on'
HDMI audio no longer functions although the device and modules seem to
load and I cannot locate any error messages. In this configuration
IOMMU functions as expected and I can successfully pass the Nvidia
card through to a KVM guest using VFIO.
As per this
(https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1223840) bug
report and the linked bugzilla thread I attempted to use kernel flag
'intel_iommu=on,igfx_off'. This resolves the HDMI audio out but
breaks IOMMU as in VGA pass through generates DMA errors.
I'm running from a clean installation of 14.10 with no modifications
to the kernel or kvm, qemu, libvirt or virt-manager.
In either scenario above the analogue audio out continues to function,
I haven't tested the optical out as I have no hardware to do so.
ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: linux-image-3.16.0-31-generic 3.16.0-31.41
ProcVersionSignature: Ubuntu 3.16.0-31.41-generic 3.16.7-ckt5
Uname: Linux 3.16.0-31-generic x86_64
ApportVersion: 2.14.7-0ubuntu8.2
Architecture: amd64
AudioDevicesInUse:
USERPID ACCESS COMMAND
/dev/snd/controlC2: kelvin 3468 F pulseaudio
/dev/snd/controlC3: kelvin 3468 F pulseaudio
/dev/snd/controlC0: kelvin 3468 F pulseaudio
/dev/snd/controlC1: kelvin 3468 F pulseaudio
CurrentDesktop: Unity
Date: Wed Mar 4 12:53:17 2015
HibernationDevice: RESUME=UUID=4d35060a-85c4-45fd-9f8e-530491588931
InstallationDate: Installed on 2015-02-26 (5 days ago)
InstallationMedia: Ubuntu-Server 14.10 "Utopic Unicorn" - Release amd64
(20141022.2)
MachineType: To Be Filled By O.E.M. To Be Filled By O.E.M.
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.16.0-31-generic.efi.signed
root=UUID=4914f227-6bb0-40bb-a781-9ad7111a996f ro intremap=no_x2apic_optout
intel_iommu=on,forcedac pci-stub.ids=10de:11c8,10de:0e0b nomdmonddf nomdmonisw
RelatedPackageVersions:
linux-restricted-modules-3.16.0-31-generic N/A
linux-backports-modules-3.16.0-31-generic N/A
linux-firmware 1.138.1
RfKill:
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 12/17/2014
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: P1.70
dmi.board.name: Z97 Extreme6
dmi.board.vendor: ASRock
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: To Be Filled By O.E.M.
dmi.chassis.version: To Be Filled By O.E.M.
dmi.modalias:
dmi:bvnAmericanMegatrendsInc.:bvrP1.70:bd12/17/2014:svnToBeFilledByO.E.M.:pnToBeFilledByO.E.M.:pvrToBeFilledByO.E.M.:rvnASRock:rnZ97Extreme6:rvr:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.:
dmi.product.name: To Be Filled By O.E.M.
dmi.product.version: To Be Filled By O.E.M.
dmi.sys.vendor: To Be Filled By O.E.M.
To manage notifications about this bug go to:
https://bugs.launchpad.net/alsa-driver/+bug/1428121/+subscriptions
--
Mailing list: https://launchpad.net/~desktop-packages
Post to : desktop-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~desktop-packages
More help : https://help.launchpad.net/ListHelp
