From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DFF38364953 for ; Thu, 3 Sep 2026 05:01:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788411693; cv=none; b=sp7HB12lj/4SIsNQHzNSlktMh2IJyteshiqe3sJgbeFxZsvXJ5ewofnWdGlCHVYNcdpxiv1ljj9JRX5Uub/WzkijPakEgeokZrXqOmYTVmxDthhmlgFtnGmLARdRw//EyBeOz749CZpdZQo4EEv2a1zXjZxFnz6M+1vjCiugf/o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788411693; c=relaxed/simple; bh=S5VKt7wz2GaOb622OCWtsz0kVZO01WUX/qp8zHO/DeM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=bGJ6iwz/zhuLHxHnFGSUx6mc+UphDIagpgKvlV5H/kYYYDN2LuQiToLTVzYCN7qAS/SPNFhpDZ6hDf4n5IQ2TFYIirYN+oFa9IxcPIsd+bO3ey8vfBtV+HeLpLtiAzR/2318YO5FxN/w6CvlJL8cGT9dTvFu5OGGokxvMoUQwSk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=nIFgOICk; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="nIFgOICk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A52311F000E9; Thu, 3 Sep 2026 05:01:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788411691; bh=2kGQPFq9LXppYE1eo2N37hwm9OvhxUE69m+em0Ygt+4=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=nIFgOICkcv+tJGMP0mvH9BvXBqaQka3h8ePajRHBdWSviBb+3DthRkbpElleLhRWq 0cUYGJw+WBorogxc7/ydKxbPHB1dqVCeyeOCPnoBdmPttGu9J7iVbjg7C/5Yj6rFCi r4SUebaf15uGkL95CnrG525RIrBjPq+Ya5bJF6JE= Date: Thu, 3 Sep 2026 06:59:46 +0200 From: Greg KH To: Melissa Wen Cc: Thorsten Leemhuis , Viktor =?iso-8859-1?Q?J=E4gersk=FCpper?= , Alex Deucher , airlied@gmail.com, alexander.deucher@amd.com, christian.koenig@amd.com, daniels@collabora.com, harry.wentland@amd.com, leandro.ribeiro@collabora.com, maarten.lankhorst@linux.intel.com, mripard@kernel.org, pekka.paalanen@collabora.com, simona@ffwll.ch, siqueira@igalia.com, sunpeng.li@amd.com, tzimmermann@suse.de, Alex Hung , Daniel Wheeler , kernel-dev@igalia.com, Lyude Paul , Timur =?iso-8859-1?Q?Krist=F3f?= , Mikhail Gavrilov , Xaver Hugl , amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Linux kernel regressions list Subject: Re: [PATCH v4 0/3] drm/atomic-state-helper: fixes for blend-mode-prop warning Message-ID: <2026090341-appraisal-jot-6aec@gregkh> References: <20260826104143.39077-1-mwen@igalia.com> <83bef197-dfbc-44a5-b9d8-6e0c44488793@igalia.com> <6dda204d-2c12-4442-9893-6449b5ce51c9@igalia.com> <9d5fa2bf-d9e4-4c6a-a9ca-8abf14ad894e@leemhuis.info> <572f78a8-1b09-4275-bca7-0ae8703776d0@freenet.de> <722d96c4-8938-4da4-9eb4-2af50b9d8b26@leemhuis.info> Precedence: bulk X-Mailing-List: regressions@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Wed, Sep 02, 2026 at 08:58:37PM +0200, Melissa Wen wrote: > > > On 01/09/2026 09:12, Thorsten Leemhuis wrote: > > On 8/28/26 14:19, Viktor Jägersküpper wrote: > > > On 8/28/26 09:22, Thorsten Leemhuis wrote: > > > > On 8/27/26 19:14, Melissa Wen wrote: > > > > > On 27/08/2026 18:37, Melissa Wen wrote: > > > > > > On 27/08/2026 15:34, Alex Deucher wrote: > > > > > > > On Wed, Aug 26, 2026 at 7:20 AM Melissa Wen wrote: > > > > > > > > PREMULTI was the default DRM blend mode until 9813e158d13d > > > > > > > > ("drm/drm_blend: allow blend mode property without PREMULTI") > > > > > > > > introduced > > > > > > > > the possibility of exposing the blend mode property without PREMULTI > > > > > > > > being supported. However, __drm_atomic_helper_plane_state_init() still > > > > > > > > resets pixel_blend_mode to PREMULTI (hardcoded), ignoring the supported > > > > > > > > mode in this property. In the same series, 860e748bddcc ("drm: ensure > > > > > > > > blend mode supported if pixel format with alpha exposed") starts > > > > > > > > warning > > > > > > > > drivers that supports alpha formats in a given planes but doesn't > > > > > > > > support blend mode property, which includes AMD primary and cursor > > > > > > > > planes. > > > > > [...] > > > > > > > I presume you are planning to apply this directly to drm-misc for 7.3? > > > > > > Right, I'll apply to drm-misc-fixes, just doing it now. > > > > > Or not now. I have to wait for -rc1. > > > > > I'll keep it on my radar. > > > > Hmmm, that sounds like these fixes will miss -rc1. But wouldn't it be > > > > good to get them included there, as they afaik (please correct me if I'm > > > > wrong, is easy to mix something up from the outside!) the warnings that > > > > Greg described as ""It's not good to boot and have a bunch of warnings > > > > already happening, resulting in a "tainted" kernel before I have the > > > > chance to break anything manually myself...""[1], as more people then > > > > will likely encounter this (and then waste time on bisecting an issue > > > > known for weeks for which a fix exists). > > > > > > > > [1] > > > > https://lore.kernel.org/all/2026082651-spinning-cornbread-33ba@gregkh/ > > > If I understand correctly, the *actual* fix (for all affected drivers) > > > will make it into 7.3-rc1, see this answer to my question: > > > https://lore.kernel.org/dri-devel/20260826-brave-nyala-of-elevation-d23aea@houat/ > > > > > > This fix is queued in drm-next: > > > https://gitlab.freedesktop.org/drm/kernel/-/commit/271e90eb5f9ff34951647e5ed33c1775eebcca50 > > Ahh, yeah, many thx, I had see this downgrade to drm_warn() (which made > > it to -rc1, yeah \o/), but had not made the right connections. :-/ > > > > FWIW, even with that done there is now one amdgpu regression report > > about this already post-rc1: > > https://lore.kernel.org/all/CANkdJ2VvJQSBzyOq=LgSW1=Z8-YiN_r9Py2iJ0UJDo55+dbfuA@mail.gmail.com/ > > > > """ > > [...] After updating from kernel v7.2.2 to v7.3-rc1, several DRM plane > > warnings regarding unset blend modes for pixel formats with alpha > > channels started appearing in dmesg during initialization. > > > > [drm] [PLANE:44:plane-0] pixel format with alpha exposed but blend > > mode not setup. Please fix. [...] > > """ > > > > Will reply there now. Wondering if we need to do something about that if > > more reports like that show up, but let's wait if that's the case. > > I just applied this series to drm-misc-fixes: > - c3080b58d81d ("drm/atomic-state-helper: set pixel_blend_mode to prop > default on reset") > - f0c75da0a6b4 ("drm/amd/display: fix missing blend-mode-prop warning for > DCN") > - 332ad707e38f ("drm/amd/display: advertise PIXEL_NONE and PREMULTI blend > mode for DCE") > > With this, the dmesg message will no longer appear on the AMD driver. Great, thanks!