Re: Cannot start Fedora 19 HVM domU with VGA passthru

["Singapore Citizen Mr. Teo En Ming (Zhang Enming)" <singapore.mr.teo.en.ming@gmail.com>]

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.
>>>
>>> Gordan
>>>
>>
>> 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.
>
> Gordan
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel
>

Dear Gordan,

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.

-- 
Yours sincerely,

Singapore Citizen Mr. Teo En Ming (Zhang Enming)