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Re: [Xen-devel] Re: vt-d p7p55d evo: Success


The last few days i played some more with the vt-d feature enabled on my system, I'm now able to passthrough an usb controller to a windows xp hvm. When i plug a usb drive into a slot controlled by that controller, windows behaves as expected. Passing through a hda-intel device (from my graphics card) seems to at least be recognised properly by windows, and windows is able to install the driver (can't verify that it is actually playing audio, since the graphics card itself can't be passed
through yet, and thus the connected monitor is in standby).
So as far as i can tell, vt-d is working fine now on this system.

Passthrough of the secondary graphics card to windows, doesn't seem to work (well, i guess that's to be expected at this stage, since i've only tried passing it through as a normal pci card, and i think it needs an extra flag set in the config
and some patches in xen, as well as passing along a bios file).
Strange thing i noticed though, when i try to boot windows with the secondary graphics card listed in its pci section, my primary X session will reset, and i'm presented the gdm
login screen... (primary & secondary graphics card are both hd4350).
Another strange thing i noticed, is that when i kill windows using xm shutdown (since it won't boot with the graphics card listed), i am not able to start it again later, not even
after removing the pci devices from the config.
Only after a machine reboot, things will work normal again.

Next on my list: try passthrough of the primary graphics card...


On Apr 9, 2010, at 1:57 AM, Mark Hurenkamp wrote:


I replaced the i5 with an i7 CPU, and now xen seems to enable vtd properly, i have yet to test the feature with my board, but xm info now shows the
hvm_directio flag:
host                   : coruscant
release                :
version                : #10 SMP PREEMPT Wed Apr 7 23:57:39 CEST 2010
machine                : x86_64
nr_cpus                : 8
nr_nodes               : 1
cores_per_socket       : 4
threads_per_core       : 2
cpu_mhz                : 3660
hw_caps                :
bfebfbff:28100800:00000000:00001b40:0098e3fd: 00000000:00000001:00000000
virt_caps              : hvm hvm_directio
total_memory           : 7975
free_memory            : 2425
node_to_cpu            : node0:0-7
node_to_memory         : node0:2425
node_to_dma32_mem      : node0:1310
max_node_id            : 0
xen_major              : 4
xen_minor              : 0
xen_extra              : .0
xen_caps               : xen-3.0-x86_64 xen-3.0-x86_32p hvm-3.0-x86_32
hvm-3.0-x86_32p hvm-3.0-x86_64
xen_scheduler          : credit
xen_pagesize           : 4096
platform_params        : virt_start=0xffff800000000000
xen_changeset : Wed Apr 07 12:38:28 2010 +0100 21091:f28f1ee587c8
xen_commandline        : console_to_ring com1=115200,8n1 console=com1
cc_compiler            : gcc version 4.4.1 (Ubuntu 4.4.1-4ubuntu9)
cc_compile_by          : root
cc_compile_domain      : karpeer.net
cc_compile_date        : Wed Apr  7 23:16:01 CEST 2010
xend_config_format     : 4


On Monday 05 April 2010 11:24:36 pm Sander Eikelenboom wrote:
Hi Mark,

I guess that's your problem, your cpu doesn't seem to support VT-D, see

Both CPU, chipset and bios most support it ...


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