Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754441AbdGSLw0 (ORCPT ); Wed, 19 Jul 2017 07:52:26 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:9316 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753890AbdGSLwX (ORCPT ); Wed, 19 Jul 2017 07:52:23 -0400 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Wed, 19 Jul 2017 04:52:21 -0700 Subject: Re: [PATCH v10] vfio: ABI for mdev display dma-buf operation To: Gerd Hoffmann , "Zhang, Tina" , "Tian, Kevin" , "linux-kernel@vger.kernel.org" , "intel-gfx@lists.freedesktop.org" , "alex.williamson@redhat.com" , "zhenyuw@linux.intel.com" , "chris@chris-wilson.co.uk" , "Lv, Zhiyuan" , "intel-gvt-dev@lists.freedesktop.org" , "Wang, Zhi A" References: <1499293795-6265-1-git-send-email-tina.zhang@intel.com> <980a5c09-fa8a-255d-19ad-acf4bb29d271@nvidia.com> <1499753648.8257.3.camel@redhat.com> <20170711091236.run4zirxmr34kazb@phenom.ffwll.local> <237F54289DF84E4997F34151298ABEBC7C57BF86@SHSMSX101.ccr.corp.intel.com> <20170712074038.izr6ureby4vwtq27@phenom.ffwll.local> <237F54289DF84E4997F34151298ABEBC7C57E3FF@SHSMSX101.ccr.corp.intel.com> <2c07d8ee-d974-33ec-2cf4-b320fc466c88@nvidia.com> <1500033939.28252.16.camel@redhat.com> <100da721-b765-ed65-7b4b-86e737e2889d@nvidia.com> <1500289405.12570.5.camel@redhat.com> <237F54289DF84E4997F34151298ABEBC7C58235A@SHSMSX101.ccr.corp.intel.com> <1500445500.29197.3.camel@redhat.com> X-Nvconfidentiality: public From: Kirti Wankhede Message-ID: Date: Wed, 19 Jul 2017 17:22:04 +0530 MIME-Version: 1.0 In-Reply-To: <1500445500.29197.3.camel@redhat.com> X-Originating-IP: [10.24.70.138] X-ClientProxiedBy: DRBGMAIL103.nvidia.com (10.18.16.22) To bgmail102.nvidia.com (10.25.59.11) Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1535 Lines: 47 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:kraxel@redhat.com] >>> Sent: Monday, July 17, 2017 7:03 PM >>> To: Kirti Wankhede ; Zhang, Tina >>> ; Tian, Kevin ; linux- >>> kernel@vger.kernel.org; intel-gfx@lists.freedesktop.org; >>> alex.williamson@redhat.com; zhenyuw@linux.intel.com; chris@chris- >>> wilson.co.uk; Lv, Zhiyuan ; intel-gvt- >>> dev@lists.freedesktop.org; Wang, Zhi A >>> 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