Re: RE: [pvops xen/next ][iommu] attenpt to passthrough PCI-e usb controllor to PV domU: (XEN) traps.c:2309:d1 Domain attempted WRMSR 000000000000008b from 00000a07:00000000 to 00000000:00000000.

[Weidong Han <weidong.han@intel.com>]

Pasi Kärkkäinen wrote:
> On Mon, Mar 22, 2010 at 05:25:55PM +0800, Weidong Han wrote:
>   
>> Pasi Kärkkäinen wrote:
>>     
>>> On Mon, Mar 22, 2010 at 05:13:33PM +0800, Weidong Han wrote:
>>>   
>>>       
>>>> Pasi Kärkkäinen wrote:
>>>>     
>>>>         
>>>>> On Mon, Mar 22, 2010 at 04:04:09PM +0800, Han, Weidong wrote:
>>>>>         
>>>>>           
>>>>>> The faults were caused by that the DMA address was not mapped in VT-d page table.
>>>>>>
>>>>>> Could you have following two tries:
>>>>>> 	1) assign it to pv domU without VT-d
>>>>>>             
>>>>>>             
>>>>> Btw are there other methods of disabling VT-d PCI passhtru than 
>>>>> having iommu=off for xen.gz in grub.conf? ie. can you somehow 
>>>>> select "use normal PV passthru for this guest" and "but still use 
>>>>> VT-d passthru for this guest" ?
>>>>>
>>>>>         
>>>>>           
>>>> I'm not quite understand your point. do you mean use normal PV 
>>>> passthru  for pv guest, but still can passthru device to hvm guest? 
>>>> if so, current  xen VT-d already does like this.
>>>>
>>>>     
>>>>         
>>> Yeah, that's what I meant. Ok. 
>>>
>>> I thought it was also possible to use VT-d for a PV guest? no?   
>>>       
>> yes. you can use VT-d to assign device to pv guest. Sander was doing  
>> that and encountered below issue.
>>
>>     
>
> Ok, so iommu=pv is the flag that enabled VT-d passthru for PV guests. 
> As a default Xen uses normal PCI passhthru for PV guests.
>
> Thanks.
>
> -- Pasi
>
>   
exactly.

Regards,
Weidong
>> Regards,
>> Weidong
>>     
>>> -- Pasi
>>>
>>>   
>>>       
>>>> Regards,
>>>> Weidong
>>>>     
>>>>         
>>>>> ps. I'm just writing a xen wiki page for PCI passthru and adding these things and the common failure scenarios there.
>>>>>
>>>>> -- Pasi
>>>>>
>>>>>         
>>>>>           
>>>>>> 	2) assign it to a hvm guest
>>>>>>
>>>>>> Regards,
>>>>>> Weidong
>>>>>>
>>>>>> -----Original Message-----
>>>>>> From: Sander Eikelenboom [mailto:linux@eikelenboom.it] Sent: 
>>>>>> Monday, March 22, 2010 5:20 AM
>>>>>> To: Konrad Rzeszutek Wilk
>>>>>> Cc: Han, Weidong; xen-devel@lists.xensource.com
>>>>>> Subject: [pvops xen/next ][iommu] attenpt to passthrough PCI-e usb controllor to PV domU: (XEN) traps.c:2309:d1 Domain attempted WRMSR 000000000000008b from 00000a07:00000000 to 00000000:00000000.
>>>>>>
>>>>>> Hi Han/Konrad,
>>>>>>
>>>>>> In my setup i'm trying to passthrough an USB 3.0 pci-e controller  to a PV domU.
>>>>>> - xen: 4.0.0-rc6
>>>>>> - dom0: kernel xen/next
>>>>>> - domU: kernel 2.6.33 from git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git
>>>>>>         ( to have pci-front together with most recent usb3.0 xhci drivers.
>>>>>>
>>>>>>
>>>>>> - USB 3.0 xhci drivers work fine on the baremetal with the 2.6.33 kernel.
>>>>>>
>>>>>> This is on a intel Q45 chipset with IOMMU.
>>>>>>
>>>>>> This is my boot config:
>>>>>> title           xen-4.0.0-rc6.gz / Debian GNU/Linux,  kernel 2.6.32
>>>>>> root            (hd0,0)
>>>>>> kernel          /boot/xen-4.0.0-rc6.gz dom0_mem=768M loglvl=all loglvl_guest=all  iommu=pv iommu_inclusive_mapping=1
>>>>>> module          /boot/vmlinuz-2.6.32 root=/dev/sda1 ro earlyprintk=xen max_loop=255 xen-pciback.hide=(03:00.0)
>>>>>> module          /boot/initrd.img-2.6.32
>>>>>>
>>>>>> When booting the domU xm dmesg gets filled with the following when the usb controller tries to initialize/:
>>>>>>
>>>>>> (XEN) traps.c:2309:d1 Domain attempted WRMSR 000000000000008b from 00000a07:00000000 to 00000000:00000000.
>>>>>> (XEN) [VT-D]iommu.c:821: iommu_fault_status: Primary Pending Fault
>>>>>> (XEN) [VT-D]iommu.c:796: DMAR:[DMA Read] Request device [03:00.0] fault addr 1ff94000, iommu reg = ffff82c3fff54000
>>>>>> (XEN) DMAR:[fault reason 06h] PTE Read access is not set
>>>>>> (XEN) print_vtd_entries: iommu = ffff83007c866970 bdf = 3:0.0 gmfn = 1ff94
>>>>>> (XEN)     root_entry = ffff83007c872000
>>>>>> (XEN)     root_entry[3] = 78f56001
>>>>>> (XEN)     context = ffff830078f56000
>>>>>> (XEN)     context[0] = 101_2f0e1001
>>>>>> (XEN)     l3 = ffff83002f0e1000
>>>>>> (XEN)     l3_index = 0
>>>>>> (XEN)     l3[0] = 2f0e0003
>>>>>> (XEN)     l2 = ffff83002f0e0000
>>>>>> (XEN)     l2_index = ff
>>>>>> (XEN)     l2[ff] = 0
>>>>>> (XEN)     l2[ff] not present
>>>>>>
>>>>>>
>>>>>>
>>>>>> Anyone any tips on what i could try ?, is this something caused by xen, or something by the usb driver not adhering to kernel DMA-api ?
>>>>>>
>>>>>> Attached:
>>>>>>
>>>>>> - xm-info.txt
>>>>>> - xm-dmesg.txt
>>>>>> - xend.log
>>>>>>
>>>>>> - dom0-dmesg.txt
>>>>>> - dom0-lspci-tree.txt
>>>>>> - dom0-lspci.txt
>>>>>>
>>>>>> - domU-lspci.txt
>>>>>> - domU-dmesg.txt
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
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>>>>>> Xen-devel@lists.xensource.com
>>>>>> http://lists.xensource.com/xen-devel
>>>>>>             
>>>>>>