Re: [Xen-users] Difference between primary and secondary VGA pass through

[Daniel Shub <Daniel.Shub@xxxxxxxxxxxxxxxx>]

> On 2 May 2014, at 10:10, "Gordan Bobic" <gordan@xxxxxxxxxx> wrote:
> 
>> On 2014-05-02 08:08, H. Sieger wrote:
>> Well, I've recently gave KVM a try and saw primary passthrough working
>> in my setup - that was until I installed the AMD driver in Windows
>> after which the guest didn't boot anymore/blue screen .
>> 
>> I believe primary passthrough can shorten the boot time of the guest,
>> but other than that I wouldn't break my head over that.
> 
> Primary passthrough re-POSTs and initializes the GPU via the BIOS.
> That means you get to see the BIOS POST and OS loading screen on
> the physical rather than emulated GPU. Other than that there is no
> difference.
> 
> The reason why primary passthrough was of interest recently was
> because ATI cards/drivers didn't handle rebooting domU gracefully,
> and re-POST-ing the card via the BIOS was a way of getting card
> back into a usable state without be driver choking on it in various
> ways. Now that the slot-level reset is being implemented, it makes
> for a simpler, more generic way to reset the card, which I guess
> takes some of the pressure for the need for primary passthrough
> for ATI cards.
> 
> Nvidia binary drivers handle the card initialization gracefully
> (provided the card's device ID is in the expensive
> Quadro/Tesla/Grid white-list - hence why a lot of us have been
> modifying various GeForce cards into equivalent Quadros) whatever
> state it was left in, so this was never an issue for those.
> 
> Gordan
> 
> _______________________________________________
> Xen-users mailing list
> Xen-users@xxxxxxxxxxxxx
> http://lists.xen.org/xen-users

Do the open source Linux ATI/Radeon drivers support FLR? When I pass my ATI 
card as a secondary device to a Linux DomU I can only get it to work with the 
proprietary Catalyst driver.This message and any attachment are intended solely 
for the addressee and may contain confidential information. If you have 
received this message in error, please send it back to me, and immediately 
delete it.   Please do not use, copy or disclose the information contained in 
this message or in any attachment.  Any views or opinions expressed by the 
author of this email do not necessarily reflect the views of the University of 
Nottingham.

This message has been checked for viruses but the contents of an attachment
may still contain software viruses which could damage your computer system, you 
are advised to perform your own checks. Email communications with the 
University of Nottingham may be monitored as permitted by UK legislation.





_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxx
http://lists.xen.org/xen-users