Re: [Xen-devel] Memory mapping for PEG/PCIe Graphics Passthrough to <any> DomU

[Fantu <fantonifabio@xxxxxxxxxx>]

I have asus p6t se (bios 0608 with vt-d enable) with core i7 920, nvidia 9800
gt and nvidia 8600 gt for passthrough.
I have installed lenny 64 bit with xen 4 from hg unstable and kernel
2.6.31.6 pv_ops from git but i was not been able to make vt-d working.
can you help me to resolve, please?

Tim Moore-13 wrote:
> 
> Hi
> 
> I have been testing xen-unstable.hg (29/03/09) over the past few days ..
> trying to enable passthrough for VGA.
> 
> I am using Debian 5.0 (lenny) x64 and compiling from source each time.
> Tried both linux-2.6.18.8 and linux-2.6.27.5 from Xenbits ...
> 
> Hardware is Nvidia Geforce 8800 512mb GTS PCIe on Intel X58 (ASUS P6T
> Deluxe) with Core i7 920 CPU.
> (had to hack the xen/drviers/pci/passthrough/vtd/dmar.c (line 388) and
> remove the DMAR bail because of bad RMRR tables.
> I also have ATI X300 PCIe for Dom0 Console.
> 
> Using Xen parameter: iommu=passthrough,pv
> Using Dom) parameter: pciback.hide=('...')
> 
> I compiled pciback as embedded in the kernel and I have tried many
> different scenarios:
> 
> 1) Nvidia Primary (hidden with pciback.hide= kernel param) (no ATI card
> installed)
> 2) ATI Primary, with Nvidia hidden (with pciback.hide= kernel param)
> 3) all scenarios with pciback as module and using echo devn >
> /sys/bus/pci/drivers/pciback/new_slot and bind
> 
> In all scenarios I can successfully see the correct PCI device in the
> DomU(s), I have tried primarily Windows XP 32bit SP3 and also:
> linux-2.6.18.8 and linux-2.6.27.5 PV and non PV kernels as DomU and
> (although I didn't load a driver) the lspci -vvv showed the devices.
> 
> Now, I progressed to installing drivers under the Win32 DomU against the
> Nvidia card, windows correctly identified the device and installed the
> driver! (latest from nvidia.com). As we all know - Windows wanted a
> reboot- beforehand a quick check of the device and it has a Yellow
> exclamation indicating reboot required and resources unavailable.
> Reboot and XP starts up ... BSOD .. nv4 driver fails .. :(
> 
> Tried with the ATI X300 Primary (no NVidia connected) and went through the
> same steps. Windows XP now boots without crash although the ATI device
> still shows a yellow exclamation and insufficient resources.
> 
> To summarise, pciback functions as expected for PCIe in Dom0 and DomU sees
> the device. All tools work fine (xm pci-attach / pci-detach / pci-list)
> and devid show and are managed correctly.
> 
> I have read all that there is on this subject and have come to the
> conclusion that this is a problem with qemu-dm and the memory mapping for
> the new Video device, the Cirrus or stdvga card is always present which I
> believe may be causing the problem. I have tried nographics=1 but qemu-dm
> still maps the Video BIOS.
> 
> Then I noticed that qemu-dm has the new options for "-vga none" .. so I
> built a wrapper script for qemu-dm to launch with this param.
> Unfortuntately the DomU doesn't startup and the qemu log does not show any
> mention of the Video memory ! so I believe the switch works, but the DomU
> then fails to boot :(
> 
> To solve this and make it usable I think some development of qemu with
> regards to the Cirrus VGA and memory management when using more than 1 vga
> controller is necessary in order to remap the Cirrus or secondary vga
> adapters in memory correctly. (its also difficult to configure a Windows
> machine for a second vga when the primary is disabled lol.)
> 
> Also, I have run strace using a qemu-dm wrapper (very verbose) and
> analysed the results -nothing seems obvious, but i`m not an expert by far
> ....
> 
> Windows has been able to support multiple VGA cards for a long time; I
> assume that MS is remapping these somehow?
> 
> I have read in 2 different places that this has worked for others before
> (without the legacy patch for igfx) and with xen-unstable.hg .. why does
> it not work for me ?
> 
> Any help / direction to further debug would be helpful .. I think many
> people would like to get this one working once and for all!
> 
> Tim
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel
> 
> 

-- 
View this message in context: 
http://old.nabble.com/Memory-mapping-for-PEG-PCIe-Graphics-Passthrough-to-%3Cany%3E-DomU-tp22783371p27026626.html
Sent from the Xen - Dev mailing list archive at Nabble.com.


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel