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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 65455C433DB for ; Mon, 15 Feb 2021 17:16:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2EE9764DE0 for ; Mon, 15 Feb 2021 17:16:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232084AbhBORQi (ORCPT ); Mon, 15 Feb 2021 12:16:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231587AbhBOQLd (ORCPT ); Mon, 15 Feb 2021 11:11:33 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5F74FC061786 for ; Mon, 15 Feb 2021 08:10:49 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=[IPv6:::1]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lBgSS-0001lW-J3; Mon, 15 Feb 2021 17:10:44 +0100 Message-ID: <21810344a6b3659e2084727a9e7950133bf294ac.camel@pengutronix.de> Subject: Re: [BUG REPORT] media: coda: mpeg4 decode corruption on i.MX6qp only From: Lucas Stach To: Sven Van Asbroeck Cc: Philipp Zabel , Nicolas Dufresne , Mauro Carvalho Chehab , Adrian Ratiu , Fabio Estevam , linux-media , Linux Kernel Mailing List Date: Mon, 15 Feb 2021 17:10:43 +0100 In-Reply-To: References: <20210203163348.30686-1-TheSven73@gmail.com> <804285cff81878a2c188d1b823182114f891ca38.camel@ndufresne.ca> <20210211143233.GA1360@pengutronix.de> <10bfc6f5aaa02ad5858186ccee1894424fc0dd39.camel@pengutronix.de> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.3 (3.38.3-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: l.stach@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Montag, dem 15.02.2021 um 10:54 -0500 schrieb Sven Van Asbroeck: > Hi Lucas, > > On Mon, Feb 15, 2021 at 5:15 AM Lucas Stach wrote: > > > > The straight forward way to fix this would be to just disable the PRE > > when the stride is getting too large, which might not work well with > > all userspace requirements, as it effectively disables the ability to > > scan GPU tiled surfaces when the stride is getting too large. > > Thank you for your very knowledgeable input, really appreciate it. > > I am wondering why I am the first to notice this particular corner > case. Is this perhaps because X+armada plugin allocate a huge bitmap > that fits all displays, and other software frameworks do not? Are > people on i.MX6 mostly using X or Wayland? If Wayland allocates a > separate bitmap for each display, this PRE bug will of course never > show up... Yep, I really doubt that there are a lot i.MX6QP, multi-display, X.Org based devices out there. While it's not anywhere in a protocol or similar fixed API, Wayland compositors mostly opted to have a separate surface per display. The weston reference compositor started out this way (as it makes surface repaint easier) and other followed the lead, so Wayland based stacks won't hit this case. Regards, Lucas