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 BF2D5C55174 for ; Wed, 5 Aug 2026 21:20:42 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3226D10EFED; Wed, 5 Aug 2026 21:20:42 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="QG604EGK"; 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 5545410EFED for ; Wed, 5 Aug 2026 21:20:41 +0000 (UTC) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 3EEA843915 for ; Wed, 5 Aug 2026 21:20:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPS id 217AEC19425 for ; Wed, 5 Aug 2026 21:20:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1785964841; bh=Pk2hZUksDyFrhN6oEJEkudP14bFcT8jmDxRs1dtce68=; h=From:To:Subject:Date:From; b=QG604EGKSpIZ/NLoE4RLSTM10z1Z53hh+jUA97obCd2SJsVKc6k1e4vjAkurKvDJa J3HjJUQTO+hgCphnM98BUOSUe8sc8qX3LCiJsVosNszP5agqSj8wUskXyjzF0UUoEa fZq35t8gzL7NuL4qX4fM8j1pSEvajbxW+QAd6mD+X+pi12KU4W/yeGI3uWOJsvyfY1 vp+qOrx/oSzh5oRchqGd/u9l66g356lwVpLU8CDOPRC7P9h8BrV4iI6H5RgCAVQogl n5/3vjYYXClyvhfukGLz142HnFEQqI83kSa5PigFIKtCVB87t9y7Joh4VpnwbycVIU 3lliAufv4wnGw== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id 05793C41612; Wed, 5 Aug 2026 21:20:41 +0000 (UTC) From: bugzilla-daemon@kernel.org To: dri-devel@lists.freedesktop.org Subject: [Bug 221838] New: [Regression] Black screen / no backlight on resume from suspend in kernel 7.0.0-28-generic (Dell Precision M4800, Optimus Intel + Quadro K1100M on nouveau) Date: Wed, 05 Aug 2026 21:20:40 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: AssignedTo drivers_video-dri@kernel-bugs.osdl.org X-Bugzilla-Product: Drivers X-Bugzilla-Component: Video(DRI - non Intel) X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: high X-Bugzilla-Who: ekonom1@atlas.sk X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: drivers_video-dri@kernel-bugs.osdl.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter cf_regression attachments.created Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" https://bugzilla.kernel.org/show_bug.cgi?id=3D221838 Bug ID: 221838 Summary: [Regression] Black screen / no backlight on resume from suspend in kernel 7.0.0-28-generic (Dell Precision M4800, Optimus Intel + Quadro K1100M on nouveau) Product: Drivers Version: 2.5 Hardware: All OS: Linux Status: NEW Severity: high Priority: P3 Component: Video(DRI - non Intel) Assignee: drivers_video-dri@kernel-bugs.osdl.org Reporter: ekonom1@atlas.sk Regression: No Created attachment 310579 --> https://bugzilla.kernel.org/attachment.cgi?id=3D310579&action=3Dedit Full system diagnostics including current dmesg, acpidump, lspci, lsusb, and kernel logs More info about bug on link https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2161214 Hi, I am experiencing a regression in the latest Ubuntu kernel package. **Hardware & GPU details:** - Laptop: Dell Precision M4800 - iGPU: Intel Corporation 4th Gen Core Processor Integrated Graphics Contro= ller - dGPU: NVIDIA Corporation GK107GLM [Quadro K1100M] (rev a1) - Driver in use: 'nouveau' (open-source kernel driver) - OS: Kubuntu 26.04 (Wayland) **Symptoms:** When waking up the laptop from suspend, the screen remains pitch black (no backlight turns on). The system is actually responsive in the background: w= hen I press my FIDO2 security key, it blinks, I can authenticate and the system unlocks, but the display output/backlight remains completely dead. **Regression confirmation:** - Kernel 7.0.0-28-generic: BROKEN (reproducible every time on resume, black screen) - Kernel 7.0.0-27-generic: OK (works perfectly, screen wakes up immediately= on resume) Since only the kernel version was changed and Mesa/KWin remained the same, = this is a clear kernel regression in the DRM/nouveau/i915 subsystem. ProblemType: Bug DistroRelease: Ubuntu 26.04 Package: linux-image-7.0.0-28-generic 7.0.0-28.28 ProcVersionSignature: Ubuntu 7.0.0-28.28-generic 7.0.12 Uname: Linux 7.0.0-28-generic x86_64 ApportVersion: 2.34.0-0ubuntu2 Architecture: amd64 CasperMD5CheckResult: unknown CurrentDesktop: KDE Date: Sat Jul 18 22:38:20 2026 InstallationDate: Installed on 2026-04-28 (81 days ago) InstallationMedia: Kubuntu 26.04 "Resolute Raccoon" - Release amd64 (202604= 23) IwDevWlp3s0Link: Not connected. MachineType: Dell Inc. Precision M4800 ProcFB: 0 i915drmfb ProcKernelCmdLine: BOOT_IMAGE=3D/vmlinuz-7.0.0-28-generic root=3DUUID=3D0865911a-d995-4fff-b0d8-34f3e26f1603 ro quiet splash PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) WifiSyslog: dmi.bios.date: 10/08/2018 dmi.bios.release: 65.25 dmi.bios.vendor: Dell Inc. dmi.bios.version: A25 dmi.board.name: 0V5GVY dmi.board.vendor: Dell Inc. dmi.board.version: A00 dmi.chassis.type: 9 dmi.chassis.vendor: Dell Inc. dmi.modalias: dmi:bvnDellInc.:bvrA25:bd10/08/2018:br65.25:svnDellInc.:pnPrecisionM4800:pv= r00:rvnDellInc.:rn0V5GVY:rvrA00:cvnDellInc.:ct9:cvr:sku05CC:pfa: dmi.product.name: Precision M4800 dmi.product.sku: 05CC dmi.product.version: 00 dmi.sys.vendor: Dell Inc. *************** INTRODUCTION AND FOCUS OF THE BUG REPORT (BUG REPORT, LINUX KERNEL, KUBUNTU) First, a quick note for the AI to ensure this transcription is correct: thi= s is a bug report regarding the Linux kernel on Kubuntu. Now, I will proceed to = the report itself. Dear developers, I would be very grateful if you could fix this bug. I real= ize that my computer is very, very old. That is one thing, but on the other han= d, Linux distributions are generally designed to support older hardware as wel= l. Therefore, I hope you will be willing to resolve this issue. NON-STANDARD SYSTEM SETTINGS AND SECURITY (FSCRYPT, SYSTEMD-HOMED, FINGERPR= INT) It is true that I have a slightly non-standard setup on Kubuntu. I have an encrypted home directory using fscrypt, and I also use systemd-homed with fingerprint authentication to unlock the computer and the login screen. It = is actually fortunate that I use this option=E2=80=94these fingerprints=E2=80= =94because it made it much easier to identify the bug and pinpoint where the error stems from. I = can assure you with absolute certainty, indeed with 100% confidence, that this = is related to the Linux kernel, specifically something in the graphics departm= ent, most likely the graphics drivers. BUG BEHAVIOR AND SYMPTOMS (BRIGHTNESS REGULATION, BLACK SCREEN, SLEEP MODE, FIDO2) It is important to supplement this bug report with additional information: whenever the very latest version of the Linux kernel is installed, it is accompanied by other symptoms. Specifically, I am unable to regulate the sc= reen brightness; it is permanently stuck, I believe, at the absolute lowest brightness level. Furthermore, as soon as I suspend the computer and wake it back up, the screen is 100% black, as if the computer were completely turned off and fails to turn on at all. We can reliably identify this as a graphics-related issue because, by looking at the flashing of the FIDO2 security key, it is possible to deduce and conclude that I have successfully logged in. There are LEDs on it that clearly signal when a successful login= has occurred. Thus, everything was working completely fine, except for the sing= le fact that the screen remained black the entire time. THANKS TO THE DEVELOPERS AND CONCLUSION (BUG FIX, SUPPORT, THANKS) So, dear developers, I wish you success in fixing this. May it cost you as little work as possible, bring a great benefit, and may you manage to fix i= t as quickly as possible with minimal effort. That is my wish for you. I wish you the best of luck and thank you, developers, for your hard work. Additionally, as a piece of supplementary information, I personally believe that slightly non-standard configurations, such as home directory encryption via systemd-homed, should not play a large or significant role in this issu= e. --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=