Re: Cannot start Fedora 19 HVM domU with VGA passthru

[Gordan Bobic <gordan@bobich.net>]

 On Thu, 18 Jul 2013 18:07:27 +0800, "Singapore Citizen Mr. Teo En Ming 
 (Zhang Enming)" <singapore.mr.teo.en.ming@gmail.com> wrote:
> On 18/07/2013 16:46, Gordan Bobic wrote:
>> On Thu, 18 Jul 2013 16:37:34 +0800, "Singapore Citizen Mr. Teo En 
>> Ming (Zhang Enming)" <singapore.mr.teo.en.ming@gmail.com> wrote:
>>
>>> Although Fedora 19 HVM domU with VGA passthrough cannot start, 
>>> Debian
>>> 7.1.0 amd64 HVM domU with VGA passthrough can start. In Debian 
>>> 7.1.0
>>> amd64 HVM domU with VGA passthrough, Intel HD Graphics 4600 is 
>>> listed
>>> in lspci -vvv. Please refer to lspci.txt. It is strange that no 
>>> kernel
>>> module is being loaded for Intel HD Graphics 4600. There is no 
>>> "Kernel
>>> driver in use" statement after VGA compatible controller: Intel
>>> Corporation Haswell Integrated Graphics Controller (rev 06) 
>>> (prog-if
>>> 00 [VGA controller]).
>>>
>>> No kernel driver is seen in lsmod. Please refer to lsmod.txt
>>>
>>> When I tried to load the kernel module by executing "modprobe 
>>> i915",
>>> it complains "no such device".
>>>
>>> ERROR: could not insert 'i915': No such device
>>>
>>> So is my Intel HD Graphics 4600 VGA Passthrough to Debian 7.1.0 
>>> amd64
>>> HVM domU considered successful since the i915 driver cannot be 
>>> loaded?
>>>
>>> Thank you very much.
>>
>> If you have a driver in dom0 claiming the device (other than the 
>> xen-pciback
>> driver), you cannot pass through that device. If you do lspci -ccc 
>> on F19
>> and you see the driver in use for that device being something other 
>> than
>> xen-pciback, that would explain why you can't pass it through.
>>
>> Also, did you first do xl pci-assignable-add for that device? This 
>> attempts
>> to detach the device from it's current driver but doesn't always 
>> work
>> especially for GPUs. The only solution is blacklist the driver for 
>> the
>> device in dom0. The downside is that you cannot run a GUI in dom0 on 
>> that
>> device.
>>
>> Gordan
>>
> Dear Gordan,
>
> I cannot start Fedora 19 HVM domU with VGA passthrough at all. Could
> you advise me on the workaround?
>
> As for the Intel HD Graphics (i915) driver, I have it blacklisted in
> /etc/modprobe.d/blacklist.conf already. Please refer to attached
> blacklist.conf.

 Have you confirm that no other driver is bound to the device in lspci 
 -vvv?
 Also what version of Xen are you running on each of the distros, and 
 which
 dom0 kernel?

 Gordan