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Re: [Qemu-devel] VFIO VGA test branches
From: |
Knut Omang |
Subject: |
Re: [Qemu-devel] VFIO VGA test branches |
Date: |
Mon, 20 May 2013 23:08:59 +0200 |
On Sun, 2013-05-19 at 23:26 +0400, Maik Broemme wrote:
> Hi Knut,
>
> Knut Omang <address@hidden> wrote:
> >
> > On Mon, 2013-05-13 at 16:23 -0600, Alex Williamson wrote:
> > > On Mon, 2013-05-13 at 22:55 +0200, Knut Omang wrote:
> > > > Hi all,
> > > >
> > > > Perfect timing from my perspective, thanks Alex!
> > > >
> > > > I spent the better part of the weekend testing your branches on a new
> > > > system
> > > > I just put together for this purpose, results below..
> > > >
> > > > On Fri, 2013-05-03 at 16:56 -0600, Alex Williamson wrote:
> > > > ...
> > > > > git://github.com/awilliam/linux-vfio.git vfio-vga-reset
> > > > > git://github.com/awilliam/qemu-vfio.git vfio-vga-reset
> > > >
> > > > System setup:
> > > >
> > > > - Fedora 18 on
> > > > - Gigabyte Z77X-UD5H motherboard
> > > > - Intel Core i7 3770 (Ivy bridge w/integrated graphics)
> > > > - 2 discrete graphics cards:
> > > >
> > > > lspci | egrep 'VGA|Audio'
> > > > 00:02.0 VGA compatible controller: Intel Corporation Xeon E3-1200
> > > > v2/3rd Gen Core processor Graphics Controller (rev 09)
> > > > 00:1b.0 Audio device: Intel Corporation 7 Series/C210 Series Chipset
> > > > Family High Definition Audio Controller (rev 04)
> > > > 01:00.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI
> > > > Caicos [Radeon HD 6450]
> > > > 01:00.1 Audio device: Advanced Micro Devices [AMD] nee ATI Caicos HDMI
> > > > Audio [Radeon HD 6400 Series]
> > > > 02:00.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI
> > > > Cape Verde PRO [Radeon HD 7700 Series]
> > > > 02:00.1 Audio device: Advanced Micro Devices [AMD] nee ATI Cape
> > > > Verde/Pitcairn HDMI Audio [Radeon HD 7700/7800 Series]
> > > >
> > > > Short summary:
> > > >
> > > > - Once I got past a few time consuming obstacles explained below
> > > > - the graphics part of the graphics/hdmi audio passthrough seems to
> > > > work perfect
> > > > on both discrete graphics cards
> > > > (though so far only one at at time and with some minor issues, see
> > > > below)
> > > > - no success with the hdmi audio yet (ideas for further
> > > > investigation appreciated!)
> > >
> > > I've had hdmi audio working with an HD7850, but only in Windows (7) and
> > > it was using legacy interrupts for some reason instead of MSI. I wonder
> > > if Liux guests might work with snd_hda_intel.enable_msi=0. I'm not sure
> > > what's wrong with MSI, but it seems to be new with the PCI bus reset
> > > support.
> >
> > In my first tries, Windows were just using a generic
> > VGA driver, which still seems to work perfect with reboots and everything
> > and in full screen resolution (1920x1200).
> > However after installing the Catalyst AMD driver stack, upon boot
> > Windows 7 now consequently get a BSOD from the graphics driver
> > with the message:
> >
> > "Attempt to reset the display driver and recover from timeout failed"
> > - a picture of the BSOD screen attached.
> >
> > I attach the corresponding vfio log where I added some timing code to
> > make it easier to see when the BSOD happens (with 2 seconds of silence
> > in the log before the VM reboots, I believe this is at 09:28:32-34 in
> > the log.
> >
> > Similar behaviour both just after reboot/power cycle of the host and
> > subsequent VM boot attempts.
> >
> > This is still with the HD7700 as passed through device, but after a
> > motherboard firmware upgrade (to F14) which did not seem to affect the
> > observed behaviour on Windows prior to Catalyst install or with Linux
> > guest, neither did it fix the bug in selecting primary devices as I
> > was hoping for.
> >
> > Let me know if you have ideas for further debugging this,
> >
>
> I had a similar problem a couple of days ago and posted it in this list.
> I got similar BSOD and tested already the following configurations:
>
> 1) machine: q35 / kvm: yes / vga: none / x-vga: on = qemu freeze
> 2) machine: q35 / kvm: no / vga: none / x-vga: on = qemu freeze
> (with errors below)
> 3) machine: q35 / kvm: yes / vga: none / x-vga: off = qemu runs with
> 100% CPU due to no VGA init (no picture)
> 4) machine: q35 / kvm: yes / vga: cirrus / x-vga: off = qemu runs with
> BOSD on loading atikmpag.sys
> 5) machine: pc / kvm: yes / vga: cirrus / x-vga: off = qemu runs fine
>
> However I've re-run the BSOD case already with the following branches
> from Alex:
>
> git://github.com/awilliam/linux-vfio.git vfio-vga-reset
> git://github.com/awilliam/qemu-vfio.git vfio-vga-reset
>
> Also with latest seabios and it worked so far. No more BSOD and reboot
> of VM was also possible without suspend / resume the host between.
Hmm, seems you have been more lucky with the choice of chipset/CPU than
me - all my tests are also with these branches but on Intel...
Knut
> > Thanks,
> >
> > Knut
> >
> > > > - Contrary to address@hidden I had no success with using pci-assign for
> > > > VGA
> > > > with a standard fedora 18 kernel and fairly recent qemu, nor with
> > > > your branches,
> > > >
> > > > Details:
> > > >
> > > > - I started off with the required kernel parameter 'intel_iommu=on' +
> > > > necessary parameters for disabling radeon
> > > > (radeon.modeset=0 rd.driver.blacklist=radeon) using the integrated
> > > > graphics as primary display
> > > > - this caused the system to freeze (with color artifacts on the
> > > > console)
> > > >
> > > > - In my naivity and because of the "i" in ifgx I tried both with
> > > > 'intel_iommu=ifgx_off' and then 'intel_iommu=on,igfx_off'
> > > > and a full set of combinations of vfio, cards, kernels and pci-assign
> > > > before I suspected
> > > > that iommu support was turned off for **all** graphics cards with
> > > > igfx_off
> > >
> > > I'm not sure why this is, looks like the code only tries to turn it off
> > > when only graphics is under the remapping device. We'd probably need to
> > > see the DMAR to know more (/sys/firmware/acpi/tables/DMAR).
> > >
> > > > - The solution was to have integrated graphics turned off in the BIOS,
> > > > and 'intel_iommu=on':
> > > >
> > > > - iommu groups:
> > > >
> > > > ls -l /sys/bus/pci/devices/0000:01:00.0/iommu_group/devices
> > > > total 0
> > > > lrwxrwxrwx 1 root root 0 May 11 08:55 0000:00:01.0 ->
> > > > ../../../../devices/pci0000:00/0000:00:01.0
> > > > lrwxrwxrwx 1 root root 0 May 11 08:55 0000:00:01.1 ->
> > > > ../../../../devices/pci0000:00/0000:00:01.1
> > > > lrwxrwxrwx 1 root root 0 May 11 08:55 0000:01:00.0 ->
> > > > ../../../../devices/pci0000:00/0000:00:01.0/0000:01:00.0
> > > > lrwxrwxrwx 1 root root 0 May 11 08:55 0000:01:00.1 ->
> > > > ../../../../devices/pci0000:00/0000:00:01.0/0000:01:00.1
> > > > lrwxrwxrwx 1 root root 0 May 11 08:55 0000:02:00.0 ->
> > > > ../../../../devices/pci0000:00/0000:00:01.1/0000:02:00.0
> > > > lrwxrwxrwx 1 root root 0 May 11 08:55 0000:02:00.1 ->
> > > > ../../../../devices/pci0000:00/0000:00:01.1/0000:02:00.1
> > > >
> > > > - eg. both the VGA/HDMI Audio pairs + the two root ports they are
> > > > plugged into are in the same group:
> > >
> > > Ick. Intel has been pretty good about advertising ACS support on their
> > > root ports. I wonder if this is an oversight or if they are actually
> > > not isolated from each other.
> > >
> > > > # lspci -n
> > > > ...
> > > > 01:00.0 0300: 1002:683f
> > > > 01:00.1 0403: 1002:aab0
> > > > 02:00.0 0300: 1002:6779
> > > > 02:00.1 0403: 1002:aa98
> > > > ...
> > > >
> > > > modprobe vfio_pci
> > > > echo 0000:01:00.1 > /sys/bus/pci/devices/0000\:01\:00.1/driver/unbind
> > > > echo 0000:02:00.1 > /sys/bus/pci/devices/0000\:02\:00.1/driver/unbind
> > > > echo 1002 683f > /sys/bus/pci/drivers/vfio-pci/new_id
> > > > echo 1002 aab0 > /sys/bus/pci/drivers/vfio-pci/new_id
> > > > echo 1002 6779 > /sys/bus/pci/drivers/vfio-pci/new_id
> > > > echo 1002 aa98 > /sys/bus/pci/drivers/vfio-pci/new_id
> > > >
> > > > # lsusb
> > > > ...
> > > > Bus 001 Device 008: ID 046d:c315 Logitech, Inc. Classic New Touch
> > > > Keyboard
> > > > Bus 001 Device 004: ID 046d:c05b Logitech, Inc. M-U0004 810-001317
> > > > [B110 Optical USB Mouse]
> > > > ...
> > > >
> > > > - I also applied your suggested patch to the quirk function in VFIO
> > > > (see below)
> > > >
> > > > - Here is a (trimmed for readability) command line I successfully used
> > > > to boot from the Windows 7 install DVD,
> > > > notice the cd and disk device descriptions and the bus parameter - I
> > > > struggled a while with that
> > > > until I came across a comment by Gerd Hoffmann here:
> > > > https://bugzilla.redhat.com/show_bug.cgi?id=922670 (Thanks, Gerd!)
> > > >
> > > >
> > > > qemu-kvm -M q35 \
> > > > -nodefconfig -readconfig $SRC/qemu/docs/q35-chipset.cfg \
> > > > -device
> > > > vfio-pci,host=2:00.0,x-vga=on,multifunction=on,bus=ich9-pcie-port-1,addr=0.0
> > > > \
> > > > -device vfio-pci,host=2:00.1,bus=ich9-pcie-port-1,addr=0.1 \
> > > > -L $SRC/seabios/out/ -L $SRC/qemu/pc-bios \
> > > > -vga none -nographic -cpu host -rtc base=localtime -k no -m 8192 -smp
> > > > 2 \
> > > > -drive file=/dev/sr0,index=2,media=cdrom,id=cd \
> > > > -drive file=ivm03.img,index=0,media=disk,id=ivm03 \
> > > > -device ide-drive,drive=ivm03,bus=ide.0 \
> > > > -device ide-cd,drive=cd,bus=ide.1 \
> > > > -net nic,vlan=0,model=virtio -net tap,vlan=0 \
> > > > -enable-kvm \
> > > > -device usb-host,hostbus=1,hostaddr=8 \
> > > > -device usb-host,hostbus=1,hostaddr=4
> > > >
> > > > - Both the graphics card seemshould really support ACS on s to have a
> > > > rom but only the HD6450 let itself to "scraping".
> > >
> > > Did you try scraping the HD6450 while the HD7700 was the boot VGA and
> > > vica versa? The boot VGA ROM is handled in a special way and what you
> > > really get is the shadow copy, which isn't what we want.
> > >
> > > > Anyway, supplying it to vfio did not seem to make any difference.
> > > >
> > > > find /sys -name rom
> > > > /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/rom
> > > > /sys/devices/pci0000:00/0000:00:01.1/0000:02:00.0/rom
> > > > ...
> > > >
> > > > Some observations and remaining unresolved issues:
> > > >
> > > > - VFIO patch:
> > > > Initially (while still running with igfx_off) I observed exactly the
> > > > same behaviour as address@hidden
> > > > reported a while ago: With vfio_pci debug enabled, vfio_pci ended up
> > > > spinning with repeated calls to
> > > > vfio_ati_3c3_quirk_read and repeated logs:
> > > > vfio: vfio_vga_read(0x3c3, 1) = 0x0
> > > > I patched up accordingly with
> > > >
> > > >
> > > > diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c
> > > > index da0e5f9..a361d06 100644
> > > > --- a/hw/misc/vfio.c
> > > > +++ b/hw/misc/vfio.c
> > > > @@ -1291,7 +1291,7 @@ static uint64_t vfio_ati_3c3_quirk_read(void
> > > > *opaque,
> > > > uint64_t data =
> > > > vfio_vga_read(&vdev->vga.region[QEMU_PCI_VGA_IO_HI],
> > > > addr + quirk->data.base_offset,
> > > > size);
> > > >
> > > > - if (data == quirk->data.address_match) {
> > > > + if (1 || data == quirk->data.address_match) {
> > > > data = vfio_pci_read_config(&vdev->pdev,
> > > > quirk->data.address_val, size);
> > > > DPRINTF("%s(0x3c3, 1) = 0x%"PRIx64"\n", __func__, data);
> > > > }
> > > >
> > > >
> > > > This of course did not help much until I actually got the iommu
> > > > enabled for the radeons (similar "repeated patters" as deniv reported)
> > > > but what I have observed after I got it working is that if
> > > > I disable the patch above, things are not that well: the Fedora VM
> > > > comes up with VGA and the Fedora boot screen, then goes blank when
> > > > switching to X.
> > >
> > > Hmm, I think we'd probably have better luck making that unconditional
> > > until we have reason to do otherwise.
> > >
> > > > - The fact that the iommu group now extends across all my available
> > > > graphics
> > > > devices now makes it difficult to get the radeon (or catalyst)
> > > > driver use to
> > > > the other card since the vfio_pci driver needs to hold it.
> > > > Not a complete showstopper since the vesa driver comes up with
> > > > 1024x768..
> > > > Might it be a good idea to have an override option (exception list or
> > > > similar?)
> > > > to allow the vfio_pci to be less restrictive about owning the whole
> > > > group
> > > > - allow functionality over security in such case? This of course is
> > > > further complicated
> > > > by the need for graphics drivers to be disabled/enabled already at
> > > > the kernel prompt..
> > >
> > > We have a quirk in the kernel that enables us to witelist devices, but
> > > yes, there is no flexibility in this w/o modifying the code and
> > > rebuilding. (see drivers/pci/quirks.c:pci_dev_acs_enabled and follow
> > > the example above w/ pci_dev_dma_source - function can just return 1)
> > >
> > > > - There seems to be a bug in the (version F8) UEFI BIOS on the
> > > > motherboard,
> > > > The BIOS offers (undocumented) a full range of selections of which
> > > > PCIe
> > > > (or PCIe 1x) graphics card to use as primary, but any other selection
> > > > than the first PCIe 16x slot has no effect and the motherboard
> > > > reverts
> > > > to the first slot, so to be able to test both cards, I had to put the
> > > > card under test
> > > > into the second (8x) PCIe slot. I am waiting for feedback from
> > > > Gigabyte on possible
> > > > fixes for this in newer BIOSes.
> > > >
> > > > - The ultimate goal is to try to consolidate some older Windows
> > > > desktops as "seats"
> > > > on the new system, using the discrete graphics with HDMI/Displayport
> > > > audio.
> > > > With the HD7700 moved to the second PCIe slot I tested both Windows
> > > > and
> > > > Linux guests to try to get some sound through the HDMI audio device.
> > > > Windows complains that no usable device is available. On Linux
> > > > (Fedora 18, KDE desktop),
> > > > the system settings -> multimedia dialogue never opens up which seems
> > > > to indicate that
> > > > PulseAudio has problems communicating with the passed through device
> > > > (?),
> > > > any hints/pointers here appreciated. From the vfio log it seems at
> > > > least
> > > > config space is accessed ok.
> > > >
> > > > - There also seems to be issues with radeon and intel_iommu=on - if I
> > > > try
> > > > to enable modesetting and normal X support for the radeon cards, X
> > > > fails to start.
> > > >
> > > > - It would be nice if the integrated graphics could be used as the host
> > > > primary display -
> > > > I would be happy if someone has any hints as to if/how the ifgx_off
> > > > option
> > > > could be extended/modified to only affect iommu operation on selected
> > > > device(s),
> > > > if at all possible..
> > >
> > > Let's see what we can discover from your DMAR. Also send along sudo
> > > lspci -vvv. Thanks,
> > >
> > > Alex
> > >
> >
> >
>
> --Maik
- Re: [Qemu-devel] VFIO VGA test branches, (continued)
- Re: [Qemu-devel] VFIO VGA test branches, Maik Broemme, 2013/05/19
- Re: [Qemu-devel] VFIO VGA test branches, Alex Williamson, 2013/05/19
- Re: [Qemu-devel] VFIO VGA test branches, Maik Broemme, 2013/05/20
- Re: [Qemu-devel] VFIO VGA test branches, Maik Broemme, 2013/05/27
- Re: [Qemu-devel] VFIO VGA test branches, Alex Williamson, 2013/05/27
- Re: [Qemu-devel] VFIO VGA test branches, Maik Broemme, 2013/05/28
- Re: [Qemu-devel] VFIO VGA test branches, Alex Williamson, 2013/05/28
- Re: [Qemu-devel] VFIO VGA test branches, Maik Broemme, 2013/05/29
- Re: [Qemu-devel] VFIO VGA test branches, Maik Broemme, 2013/05/29
- Re: [Qemu-devel] VFIO VGA test branches, Alex Williamson, 2013/05/29
- Re: [Qemu-devel] VFIO VGA test branches,
Knut Omang <=
- Re: [Qemu-devel] VFIO VGA test branches, Alex Williamson, 2013/05/20
- Re: [Qemu-devel] VFIO VGA test branches, Knut Omang, 2013/05/20
- Re: [Qemu-devel] VFIO VGA test branches, Knut Omang, 2013/05/28
- Re: [Qemu-devel] VFIO VGA test branches, Alex Williamson, 2013/05/28
Re: [Qemu-devel] VFIO VGA test branches, Justin Gottula, 2013/05/11