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=-8.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, 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 7D557C43387 for ; Wed, 9 Jan 2019 11:37:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E26321783 for ; Wed, 9 Jan 2019 11:37:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547033856; bh=FF2vd1Obk2LeuFU+5+bxuooqtBDJR4hsSNBOpm7rfoY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=krsqr5+Wwb+JrO5Gx0bhtL3SJOsyQW2sc//uzUvdi3l9E51HBB3TsyGqTyI7rl4u8 zUeDAirWRpww7EzlBlhgSsep3JHiZsdKRfVKh/RTtqyqoqG3HrKs4P+R03VkQZtNCV FEUkmI57EX09z88oLl4f80jtlvxg04casRjY9LIM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730893AbfAILhf (ORCPT ); Wed, 9 Jan 2019 06:37:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:54264 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730873AbfAILhf (ORCPT ); Wed, 9 Jan 2019 06:37:35 -0500 Received: from bbrezillon (91-160-177-164.subs.proxad.net [91.160.177.164]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 93C9120652; Wed, 9 Jan 2019 11:37:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547033854; bh=FF2vd1Obk2LeuFU+5+bxuooqtBDJR4hsSNBOpm7rfoY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=KVjKborKe/gIozUUHRef5iPMjxgX58tnVh3S0ysqkrsVZ75juHeFYuG8fYsWFK/uI 7EjqXaXHAgoyiqwJq9JoTDxbE3UfmAGxS6BchIPSxOwMC9zbJ3lbCqRbzs10t6mTp6 bgChlnIcn9CYqDsWvHpsWs2iBOtrlZG8i0UqPj1A= Date: Wed, 9 Jan 2019 12:37:24 +0100 From: Boris Brezillon To: Daniel Vetter Cc: Peter Rosin , Alexandre Belloni , David Airlie , "linux-kernel@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , Nicolas Ferre , Boris Brezillon , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH] drm/atmel-hlcdc: prevent divide by zero Message-ID: <20190109123449.65742b99@bbrezillon> In-Reply-To: <20190109101224.GT21184@phenom.ffwll.local> References: <20190108123129.20031-1-peda@axentia.se> <20190109101224.GT21184@phenom.ffwll.local> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 9 Jan 2019 11:12:24 +0100 Daniel Vetter wrote: > On Tue, Jan 08, 2019 at 12:31:36PM +0000, Peter Rosin wrote: > > While trying to temporarily hide a plane, one thing that was attempted > > was to call (from libdrm) > > > > drmModeSetPlane(fd, plane_id, crtc_id, fb_id, 0, > > 0, 0, 0, 0, 0, 0, 0, 0); > > > > This call causes a pair of "Division by zero in kernel." messages. Kill > > those messages, but preserve the current behaviour that also happen to > > make the plane disappear with the above call. > > > > Signed-off-by: Peter Rosin > > --- > > drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_plane.c | 14 ++++++++++---- > > 1 file changed, 10 insertions(+), 4 deletions(-) > > > > Side note, when comparing with drm_atomic_helper_check_plane_state(), I get > > the feeling that the src rect should be clipped together with the crtc rect > > if/when clipping is needed. That function calls drm_rect_clip_scaled(), and > > the equivalent does not seem to happen here. Should clipping be performed > > on the src rect? > > Any reasons atmel can't switch over to that helper? Would compute a nice > ->visible state variable for you ... We should definitely use drm_atomic_helper_check_plane_state().