Re: Cannot start Fedora 19 HVM domU with VGA passthru

[Gordan Bobic <gordan@bobich.net>]

 On Thu, 18 Jul 2013 18:20:08 +0800, "Singapore Citizen Mr. Teo En Ming 
 (Zhang Enming)" <singapore.mr.teo.en.ming@gmail.com> wrote:
> On 18/07/2013 18:09, Gordan Bobic wrote:
>> 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.
>>>
>>> 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?
>
> I have checked "lsmod | grep i915" and the command doesn't return
> anything, which means the kernel module i915 is not loaded in dom0.

 Check lspci -vvv,find the device in the output and look for the lines 
 that say:
 Kernel driver in use:
 Kernel modules:

 The kernel driver might not be called the same thing in both kernels.

> I am running Xen 4.4-unstable changeset 27238 with Linux kernel
> 3.11.0-rc1 on a Ubuntu 13.04 host.

 And on F19?

 Gordan