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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C709FC61DBE for ; Tue, 25 Aug 2026 11:07:51 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 26C3210E132; Tue, 25 Aug 2026 11:07:51 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="n8Yi0aWy"; dkim-atps=neutral Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id A3C9710E132 for ; Tue, 25 Aug 2026 11:07:50 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 44D2F40068; Tue, 25 Aug 2026 11:07:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 054AB1F000E9; Tue, 25 Aug 2026 11:07:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787656070; bh=EnKR26LQb9Tlx63aWed1RgyrV9jxjVT4jbK2UfS4014=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=n8Yi0aWyW6iYU9/DKLwBOyY+LKAu42g1mvPYO1AfH4Fy0HmCisniFljHBjg7sDpvW 6aLFzAxKxWb/cjTdl4mvu5cbzNdGw6K+U4RHl9ynPnqE9e3nkESF0ir5REwJOWglDj o1ZUdTrM+HVcslTIaQspcgiNg03PKrIYEFaI6BMZP9xgh90ukYCas5x3VPRFKcizx2 mpUbwXKkWEyKGk0RtDNX0xBIc85IjPRooWFT93QYTlH7lkZZO/l4q1RbjuqjLAjTar LGbML+7Q92P5McnbmmpyyoCaKVqNTPGSk3PZ/FJMnnsasFLxoX2bzJNu1MtX7oaEIZ NcGWsyNq1+i0A== From: sashiko-bot@kernel.org Subject: Re: [PATCH] drm/pl111: Advertise no pixel blending To: "Roshan Kumar" Cc: dri-devel@lists.freedesktop.org In-Reply-To: <20260825105427.686619-1-roshaen09@gmail.com> References: <20260825105427.686619-1-roshaen09@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 25 Aug 2026 11:07:49 +0000 Message-Id: <20260825110750.054AB1F000E9@smtp.kernel.org> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: - [High] The initial atomic plane state defaults to an invalid pixel blend = mode, which contradicts the newly added blend mode property that only suppo= rts `DRM_MODE_BLEND_PIXEL_NONE`. -- --- Patch [1]: [PATCH] drm/pl111: Advertise no pixel blending --- commit e96a716603035744ccddd019e74ade69db24a36e Author: Roshan Kumar drm/pl111: Advertise no pixel blending This commit adds a pixel blend mode property to the PL111 display plane to satisfy validation introduced in commit 860e748bddcc, advertising only DRM_MODE_BLEND_PIXEL_NONE. This resolves a syzkaller panic during boot on vexpress-a15 managers. Link: https://github.com/google/syzkaller/issues/7805 > diff --git a/drivers/gpu/drm/pl111/pl111_display.c b/drivers/gpu/drm/pl11= 1/pl111_display.c > index 5d10bc5fdf1f6..758b297cbdea5 100644 > --- a/drivers/gpu/drm/pl111/pl111_display.c > +++ b/drivers/gpu/drm/pl111/pl111_display.c [ ... ] > @@ -596,5 +597,10 @@ int pl111_display_init(struct drm_device *drm) > if (ret) > return ret; > =20 > + ret =3D drm_plane_create_blend_mode_property(&priv->pipe.plane, > + BIT(DRM_MODE_BLEND_PIXEL_NONE)); [Severity: High] Will this cause atomic commits to fail with -EINVAL for standard userspace compositors? Because pl111 uses drm_simple_display_pipe_init() and lacks a custom reset_plane hook, the DRM core falls back to drm_atomic_helper_plane_reset() which unconditionally sets plane_state->pixel_blend_mode =3D=20 DRM_MODE_BLEND_PREMULTI during __drm_atomic_helper_plane_state_init(). Since this newly created property only supports DRM_MODE_BLEND_PIXEL_NONE, userspace reading the initial state and submitting it back will provide an enum value that is not in the allowed mask. This causes=20 drm_property_change_valid_get() to reject the commit.=20 Does the driver need a custom reset hook to initialize the plane state to DRM_MODE_BLEND_PIXEL_NONE instead of relying on the default initialization? > + if (ret) > + return ret; > + > return 0; > } --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260825105427.6866= 19-1-roshaen09@gmail.com?part=3D1