From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 74D73C3279B for ; Wed, 4 Jul 2018 07:26:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2D25224680 for ; Wed, 4 Jul 2018 07:26:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2D25224680 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753719AbeGDH0q (ORCPT ); Wed, 4 Jul 2018 03:26:46 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:36264 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753046AbeGDH0o (ORCPT ); Wed, 4 Jul 2018 03:26:44 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: tomeu) with ESMTPSA id 370CC2611BF Subject: Re: [PATCH v6] Add udmabuf misc device To: Gerd Hoffmann , dri-devel@lists.freedesktop.org, David Airlie , Laurent Pinchart , Jonathan Corbet , Sumit Semwal , Shuah Khan , "open list:DOCUMENTATION" , open list , "open list:DMA BUFFER SHARING FRAMEWORK" , "moderated list:DMA BUFFER SHARING FRAMEWORK" , "open list:KERNEL SELFTEST FRAMEWORK" , Zach Reizner , Daniel Stone References: <20180703075359.30349-1-kraxel@redhat.com> <20180703083757.GG7880@phenom.ffwll.local> <20180704055338.n3b7oexltaejqmcd@sirius.home.kraxel.org> From: Tomeu Vizoso Message-ID: <9818b301-9c9d-c703-d4fe-7c2d4d43ed66@collabora.com> Date: Wed, 4 Jul 2018 09:26:39 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180704055338.n3b7oexltaejqmcd@sirius.home.kraxel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/04/2018 07:53 AM, Gerd Hoffmann wrote: > On Tue, Jul 03, 2018 at 10:37:57AM +0200, Daniel Vetter wrote: >> On Tue, Jul 03, 2018 at 09:53:58AM +0200, Gerd Hoffmann wrote: >>> A driver to let userspace turn memfd regions into dma-bufs. >>> >>> Use case: Allows qemu create dmabufs for the vga framebuffer or >>> virtio-gpu ressources. Then they can be passed around to display >>> those guest things on the host. To spice client for classic full >>> framebuffer display, and hopefully some day to wayland server for >>> seamless guest window display. >>> >>> qemu test branch: >>> https://git.kraxel.org/cgit/qemu/log/?h=sirius/udmabuf >>> >>> Cc: David Airlie >>> Cc: Tomeu Vizoso >>> Cc: Laurent Pinchart >>> Cc: Daniel Vetter >>> Signed-off-by: Gerd Hoffmann >> >> I think some ack for a 2nd use-case, like virtio-wl or whatever would be >> really cool. To give us some assurance that this is generically useful. > > Tomeu? Laurent? Sorry, but I think I will need some help to understand how this could help in the virtio-wl case [adding Zach Reizner to CC]. Any graphics buffers that are allocated with memfd will be shared with the compositor via wl_shm, without need for dmabufs. Daniel Stone [added to CC] commented though that this could be useful for browsers that composite pages with a nested Wayland compositor, to avoid having to blit each layer so that the EGL platform notifies the compositor of new contents. Cheers, Tomeu >> Plus an ack from dma-buf folks (nag them on irc, you don't have them on Cc >> here). > > Hmm, does MAINTAINERS need an update then? Maintainer and mailing lists > listed in the "DMA BUFFER SHARING FRAMEWORK" entry are on Cc. > > Who should be Cc'ed? > >> Then this is imo good to go. >> >> I assume you'll push it to drm-misc, like all the other dma-buf stuff? > > Can do that, sure, after collecting the acks ... > > thanks, > Gerd >