On 7/19/2017 11:55 AM, Gerd Hoffmann wrote: > On Wed, 2017-07-19 at 00:16 +0000, Zhang, Tina wrote: >>> -----Original Message----- >>> From: Gerd Hoffmann [mailto:[email protected]] >>> Sent: Monday, July 17, 2017 7:03 PM >>> To: Kirti Wankhede <[email protected]>; Zhang, Tina >>> <[email protected]>; Tian, Kevin <[email protected]>; linux- >>> [email protected]; [email protected]; >>> [email protected]; [email protected]; chris@chris- >>> wilson.co.uk; Lv, Zhiyuan <[email protected]>; intel-gvt- >>> [email protected]; Wang, Zhi A <[email protected]> >>> Subject: Re: [PATCH v10] vfio: ABI for mdev display dma-buf >>> operation >>> >>> Hi, >>> >>>> No need of flag here. If vGPU driver is not loaded in the guest, >>>> there >>>> is no surface being managed by vGPU, in that case this size will >>>> be >>>> zero. >>> >>> Ok, we certainly have the same situation with intel. When the >>> guest driver is not >>> loaded (yet) there is no valid surface. >>> >>> We should cleanly define what the ioctl should do in that case, so >>> all drivers >>> behave the same way. >>> >>> I'd suggest that all fields defining the surface (drm_format, >>> width, height, stride, >>> size) should be set to zero in that case. >> >> Yeah, it's reasonable. How about the return value? Currently, the >> ioctl also returns "-ENODEV" in that situation. > > I think it should not return an error. Querying the plane parameters > worked fine. >
Sounds good to me too. Thanks, Kirti
