Re: How vital is having "FLReset+" for VGA Passthru in DomU?

[cyberhawk001@gmail.com]

On 6/29/2012 6:12 PM, Rolu wrote:
> On Fri, Jun 29, 2012 at 11:47 PM,  <cyberhawk001@gmail.com> wrote:
>> On 6/29/2012 4:23 PM, Rolu wrote:
>>> On Fri, Jun 29, 2012 at 9:44 PM,  <cyberhawk001@gmail.com> wrote:
>>>> I was reading the Wiki page here: http://wiki.xen.org/wiki/VTd_HowTo
>>>> don't
>>>> know how updated it is, BUT at the top it said:
>>>> -------------------- -------------------- --------------------
>>>> -------------------- -------------------- --------------------
>>>>
>>>> Xen 4.1 xl tools notes
>>>>
>>>> Only devices with FLR capabilities are supported.
>>>> Passing through a PCI card without FLR capability will result an error.
>>>>
>>>> To check if your PCI devices have FLR function, check in this wiki, [How
>>>> can
>>>> I check if PCI device supports FLR (Function Level Reset) ?]
>>>>
>>>> If you see output with "FLReset-" then your PCI device don't support FLR
>>>> function. If output have "FLReset+" then it does.
>>>>
>>>> As this time of writing, June 2012, there are very very few PCI devices
>>>> support FLR function.
>>>> -------------------- -------------------- --------------------
>>>> -------------------- -------------------- --------------------
>>>>
>>>>
>>>> THAN was reading here:
>>>>
>>>> http://wiki.xen.org/wiki/Xen_PCI_Passthrough#How_can_I_check_if_PCI_device_supports_FLR_.28Function_Level_Reset.29_.3F
>>>> at the bottom of the page where it says:
>>>>
>>>> -------------------- -------------------- --------------------
>>>> -------------------- -------------------- --------------------
>>>>
>>>> How can I check if PCI device supports FLR (Function Level Reset)?
>>>>
>>>> Run "lspci -vv" (in dom0) and check if the device has "FLReset+" in the
>>>> DevCap field.
>>>>
>>>> If you are Ubuntu/Debian user don't forget to add sudo at front,
>>>> otherwise,
>>>> you won't get the result you should get.
>>>>
>>>> sudo lspci -vv | egrep -i --colour flreset
>>>>
>>>> The above line should get root access for lspci program and show colour
>>>> with
>>>> flreset it found from output
>>>>
>>>> -------------------- -------------------- --------------------
>>>> -------------------- -------------------- --------------------
>>>>
>>>> I did that and ALL of my devices it listed showed "FLReset-", there were
>>>> only 3x "Etron Technology, Inc. EJ168 USB3.0" controllers that showed
>>>> "FLReset+"
>>>>
>>>> SO, I have been trying to get my ATI FirePro V7900 Video Card to passthru
>>>> to
>>>> a Windows 7 Ultimate DomU with no luck so far AND was wondering how
>>>> critical
>>>> was for that device to show as "FLReset+"?
>>>>
>>>> 1.) Since my VGA card and AUDIO component of it, shows up as "FLReset-",
>>>> does that mean it is impossible to get it fully working in a Win7 DomU?
>>> I have a video card (Radeon HD 6670) with FLReset- passed through to a
>>> linux domU as a secondary video card (i.e. it boots from the built in
>>> emulated card, not the Radeon) and it works. The FLReset doesn't seem
>>> mandatory.
>>>
>>> I am running the latest xen 4.2 unstable though.
>>
>>
>> SO, what DomU are you using? That means you were able to install the Video
>> drivers inside the DomU for your HD6670 card and you can reboot the DomU
>> without issues and video still works?
> Ubuntu 12.04, with ATI's drivers. Yes, it works.
>
>>>> 2.) Does having the feature "FLReset+" depend on the motherboard BIOS,
>>>> motherboard hardware or the BIOS onboard the Video Card that could be
>>>> updated to get back the "FLReset+" so you can have the FLR reset
>>>> functionality?
>>> I think it depends on the card's hardware. It has to implement this
>>> functionality. A firmware update for the card could maybe add it, but
>>> I haven't heard of any that do.
>>
>> Ya, so far i have not read or heard about this feature, BUT i know the FLR
>> rest issues is quite the problem with Windows VMs, probably the same thing i
>> am having issues with not working. Once i boot into Win7, install the ATI
>> drivers, than reboot the DomU, and it just hangs at the "Starting Windows"
>> black screen and never gets past it. I have read a bunch of things and will
>> do more trial and error things, but for now just wondered about that
>> "FLReset+" as stated on Wiki.
>>
> I don't have a windows 7 VM so I don't know if windows has a problem
> with it. Are you using it as a primary or secondary video card?
> Secondary seems easier to get to work.
>
SO i have heard, but I have been trying to get it to work using 
Secondary VGA Passthru. I tried Primary once and, for a lack of a better 
term, all hell broke loose during DomU boot as QEMU pretty much shut 
down....lol. Granted, i didn't try very hard and didn't apply any 
patched or anything, maybe some day if that feature is a bit more stable 
and there are actual guides on how to make it work, i will try again than.

It probably doesn't make any difference, BUT at the first set of trial 
and error, i had a GeForce 7600GS in PCIex16 Slot#1 so i have video in 
Dom0, than had my ATI FirePro V7900 in the PCIex16 Slot#2 hidden to 
passthru. Now i am trying it with the ATI FirePro V7900 in the PCIex16 
Slot#1 and an older PCI VGA card so i have video in Dom0.

I am using Xen 4.2 Rev25494, so almost the latest. For now i am only 
trying to get Win7 DomU to work, later on will move to Ubuntu. I do know 
that Windows has a lot of issues with FLR and not resetting the VGA 
card, just have to find the right steps to make it get over it. My 
USB3.0 works fine and no issues being passed thru, SO figured since that 
was the only PCI device that had "FLReset+", maybe that was making it 
work correctly as compared to VGA.

BUT, thanks for the reply and i will keep playing with it til i get 
something to work.