[Bug 2169102] Re: [Regression] Window flickering and blanking on Electron/Chromium apps under Wayland with legacy radeon driver (Radeon HD 7670M) on kernel 7.0.0-34-generic

** Attachment added: "ERROR.mp4" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2169102/+attachment/6004606/+files/ERROR.mp4 -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2169102 Title: [Regression] Window flickering and blanking on Electron/Chromium apps under Wayland with legacy radeon driver (Radeon HD 7670M) on kernel 7.0.0-34-generic Status in linux package in Ubuntu: New Bug description: Problem Description: After updating to kernel 7.0.0-34-generic, specific applications (specifically Chromium/Electron-based apps with hardware acceleration enabled) experience severe window flickering, blanking, and intermittent black screens during redraws. The desktop shell remains responsive, but the client window contents intermittently fail to present or render black frames. Hardware & Environment Information: - Host: Toshiba Satellite S855 - Kernel: 7.0.0-34-generic - Display Server: Wayland (echo $XDG_SESSION_TYPE -> wayland) - GPU: AMD/ATI Thames [Radeon HD 7500M/7600M Series] (Radeon HD 7670M) [1002:6840] (rev ff) - Subsystem: Toshiba Corporation [1179:fb22] - Active Driver: radeon (DRM 2.51.0 / KMS Turks) Relevant dmesg / DRM logs: [drm] radeon kernel modesetting enabled. [drm] initializing kernel modesetting (TURKS 0x1002:0x6840 0x1179:0xFB22 0x00). [drm] Detected VRAM RAM=2048M, BAR=256M [drm] Loading TURKS Microcode radeon 0000:01:00.0: [drm] PCIE GART of 1024M enabled. radeon 0000:01:00.0: [drm] fb0: radeondrmfb frame buffer device Steps to Reproduce: 1. Boot with kernel 7.0.0-34-generic into a default Wayland session. 2. Launch a hardware-accelerated application (e.g., Google Chrome, Gemini PWA/Electron, VS Code). 3. Interact with the window or hover over UI elements. 4. The window content rapidly flickers between the rendered page and solid black. Expected Behavior: Window surfaces should redraw cleanly without buffer flickering or black frames under the legacy radeon KMS driver. Observed Behavior: Window rendering intermittently collapses to a black surface during buffer swaps under Wayland. Regression: This issue was introduced with the recent kernel update. ProblemType: Bug DistroRelease: Ubuntu 26.04 Package: linux-image-7.0.0-34-generic 7.0.0-34.34 ProcVersionSignature: Ubuntu 7.0.0-34.34-generic 7.0.14 Uname: Linux 7.0.0-34-generic x86_64 ApportVersion: 2.34.1-0ubuntu0.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: daby 4597 F.... wireplumber /dev/snd/controlC1: daby 4597 F.... wireplumber /dev/snd/seq: daby 4581 F.... pipewire CasperMD5CheckResult: pass CurrentDesktop: ubuntu:GNOME Date: Wed Sep 30 17:17:42 2026 InstallationDate: Installed on 2025-02-25 (583 days ago) InstallationMedia: Ubuntu 24.04.2 LTS "Noble Numbat" - Release amd64 (20250215) IwDevWlp8s0Link: Not connected. MachineType: TOSHIBA Satellite S855 ProcEnviron: LANG=es_ES.UTF-8 PATH=(custom, no user) SHELL=/bin/bash TERM=xterm-256color XDG_RUNTIME_DIR=<set> ProcFB: 0 radeondrmfb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-7.0.0-34-generic root=/dev/mapper/ubuntu--vg-ubuntu--lv ro quiet splash crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 04/15/2013 dmi.bios.release: 6.70 dmi.bios.vendor: Insyde Corp. dmi.bios.version: 6.70 dmi.board.name: Portable PC dmi.board.vendor: TOSHIBA dmi.board.version: MP dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 10 dmi.chassis.vendor: OEM Chassis Manufacturer dmi.chassis.version: OEM Chassis Version dmi.ec.firmware.release: 6.20 dmi.modalias: dmi:bvnInsydeCorp.:bvr6.70:bd04/15/2013:br6.70:efr6.20:svnTOSHIBA:pnSatelliteS855:pvrPSKFWU-002002:rvnTOSHIBA:rnPortablePC:rvrMP:cvnOEMChassisManufacturer:ct10:cvrOEMChassisVersion:skuPSKFWU:pfaDakar10F/FG: dmi.product.family: Dakar 10F/FG dmi.product.name: Satellite S855 dmi.product.sku: PSKFWU dmi.product.version: PSKFWU-002002 dmi.sys.vendor: TOSHIBA To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2169102/+subscriptions