Re: Cannot start Fedora 19 HVM domU with VGA passthru

[Gordan Bobic <gordan@bobich.net>]

 On Thu, 18 Jul 2013 21:13:54 +0800, "Singapore Citizen Mr. Teo En Ming 
 (Zhang Enming)" <singapore.mr.teo.en.ming@gmail.com> wrote:
> On 18/07/2013 21:04, Gordan Bobic wrote:
>> On Thu, 18 Jul 2013 20:57:55 +0800, "Singapore Citizen Mr. Teo En 
>> Ming (Zhang Enming)" <singapore.mr.teo.en.ming@gmail.com> wrote:
>>> On 18/07/2013 20:35, Gordan Bobic wrote:
>>>> On Thu, 18 Jul 2013 20:29:41 +0800, "Singapore Citizen Mr. Teo En 
>>>> Ming (Zhang Enming)" <singapore.mr.teo.en.ming@gmail.com> wrote:
>>>>> On 18/07/2013 20:03, Gordan Bobic wrote:
>>>>>> On Thu, 18 Jul 2013 19:23:58 +0800, "Singapore Citizen Mr. Teo 
>>>>>> En Ming (Zhang Enming)" <singapore.mr.teo.en.ming@gmail.com> 
>>>>>> wrote:
>>>>>>> On 18/07/2013 19:02, Gordan Bobic wrote:
>>>>>>>> On Thu, 18 Jul 2013 18:55:55 +0800, "Singapore Citizen Mr. Teo 
>>>>>>>> En Ming (Zhang Enming)" <singapore.mr.teo.en.ming@gmail.com> 
>>>>>>>> wrote:
>>>>>>>>> On 18/07/2013 18:44, Gordan Bobic wrote:
>>>>>>>>>> On Thu, 18 Jul 2013 18:40:51 +0800, "Singapore Citizen Mr. 
>>>>>>>>>> Teo En Ming (Zhang Enming)" 
>>>>>>>>>> <singapore.mr.teo.en.ming@gmail.com> wrote:
>>>>>>>>>>> On 18/07/2013 18:29, Gordan Bobic wrote:
>>>>>>>>>>>> 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:
>>>>>>>>
>>>>>>>> [...]
>>>>>>>>
>>>>>>>>>>> I have checked lspci -vvv in Ubuntu 13.04 dom0 and the 
>>>>>>>>>>> Kernel driver
>>>>>>>>>>> in use is pciback for Intel HD Graphics 4600 IGD.
>>>>>>>>>>>
>>>>>>>>>>> As for Fedora 19 HVM domU, I don't know because I cannot 
>>>>>>>>>>> start it.
>>>>>>>>>>
>>>>>>>>>> Starting is not required to do this. Do it before starting 
>>>>>>>>>> the domU.
>>>>>>>>>
>>>>>>>>> Sorry, I don't understand what you're trying to say.
>>>>>>>>
>>>>>>>> On F19, don't worry about starting the domU. In dom0, do lspci 
>>>>>>>> -vvv,
>>>>>>>> find the Intel graphics device in the output and find what 
>>>>>>>> kernel
>>>>>>>> driver / module are bound to it, if any. You can only pass 
>>>>>>>> through
>>>>>>>> a PCI device that is connected to the xen pciback driver, and 
>>>>>>>> even
>>>>>>>> then often only if no other driver had connected to the device 
>>>>>>>> first
>>>>>>>> since that might leave it in an unknown state.
>>>>>>>>
>>>>>>>
>>>>>>> But I can only start Fedora 19 HVM domU with-out vga 
>>>>>>> passthrough. I
>>>>>>> want to be able to start Fedora 19 HVM domU with vga 
>>>>>>> passthrough.
>>>>>>
>>>>>> You are trying to get one step ahead of what I am talking about.
>>>>>> Forget domU for the moment. Before you can even begin thinking
>>>>>> about the domU you have to make sure the device is available
>>>>>> for assigning in dom0. If you have a driver bound to the device
>>>>>> in dom0 you cannot pass it through to domU. So forget domU until
>>>>>> you have actually confirmed there is no driver bound to the
>>>>>> device in dom0.
>>>>>>
>>>>>> What do the following two lines say for the device in lspci -vvv
>>>>>> in _dom0_ on Fedora:
>>>>>> Kernel driver in use:
>>>>>> Kernel modules:
>>>>>>
>>>>> I have attached the output of lspci -vvv in Ubuntu 13.04 dom0. 
>>>>> The
>>>>> filename of the attachment is dom0-lspci.txt.
>>>>
>>>> You need to do this as root, otherwise some of the output is 
>>>> missing.
>>>>
>>>> And the dump from the machine where you have domU working isn't
>>>> useful, you need to post the same lspci dump from the system
>>>> where it _doesn't_ work.
>>>>
>>>
>>> I have attached the output of lspci -vvv as root in Ubuntu 13.04
>>> dom0. The filename of the attachment is root-dom0-lspci.txt.
>>
>> Right, that is showing
>> Kernel driver in use: pciback
>> for the Intel VGA device.
>>
>> But that is expected, you said you have it working on Ubuntu.
>> You now need to make sure you have the same lspci output on
>> Fedora dom0 before you start the domU.
>>
> I think you are confused. I only have *one* dom0, which is the Ubuntu
> 13.04 dom0. I don't have any other dom0.
>
> What I am trying to do is to start Fedora 19 HVM domU in Ubuntu 13.04
> dom0, but am unable to.
>
> Hope this clears everything.

 It does, thanks. I was under the impression you were dual booting dom0s
 and one was letting you boot domU and the other wasn't. Apologies.

 Gordan