Chrome Canary: Mojo Use EventFD causing persistent crash on Kernel 7.0-rc5

[Rakstrooper]

system Environment:

OS: CachyOS (Arch-based)

Kernel: 7.0.0-rc5-2-cachyos-rc

Desktop Environment: COSMIC (Wayland Native)

Browser Version: Google Chrome Canary 148.0.7760.0

GPU: Intel(R) HD Graphics 5500 (Broadwell / Dev ID: 0x1616)

Graphics Stack: Mesa 26.1.0-devel (git-8367776c9b)

Windowing System: Wayland (Ozone)

. Primary Regression: Mojo IPC / Network Service
Symptom: Enabling #mojo-use-eventfd results in an infinite crash loop of the Network Service.
Log Evidence:

Plaintext
[content/browser/network_service_instance_impl.cc:703] Network service crashed or was terminated, restarting service.
[systemd] app-com.google.Chrome.canary.scope: Process 270852 (chrome) dumped core.
Technical Analysis: Under Kernel 7.0-rc5, the eventfd signaling used by Mojo appears to trigger a sandbox violation or a kernel panic in the Network Service process, specifically when trying to pass file descriptors between the Browser and Network processes.

2. GPU Backend Incompatibility (Ozone-Wayland)
   Symptom: Chromium fails to initialize Vulkan or Skia Graphite, even when explicitly forced.
   Log Evidence:

Plaintext
[ERROR:ui/ozone/platform/wayland/gpu/wayland_surface_factory.cc:252] '--ozone-platform=wayland' is not compatible with Vulkan.
[ERROR:gpu/config/gpu_finch_features.cc:645] Enabling Graphite on a not-yet-supported platform is disallowed for safety.
Technical Analysis: The WaylandSurfaceFactory in the Ozone abstraction layer is rejecting Vulkan initialization. This suggests a breakage in the Wayland-Vulkan-Mesa bridge for Intel Broadwell hardware on the 7.0 kernel series.

3. EGL / Dawn Initialization Failure
   Symptom: Fallback to OpenGL fails with version mismatches.
   Log Evidence:

Plaintext
[ERROR:ui/gl/egl_util.cc:92] EGL Driver message (Error) eglCreateContext: Requested version is not supported.
Warning: eglCreateContext failed with EGL_BAD_ATTRIBUTE - While trying to discover a BackendType::OpenGL adapter.
Warning: maxDynamicUniformBuffersPerPipelineLayout artificially reduced from 500000 to 16.
Technical Analysis: Dawn's OpenGL discovery is failing. The EGL driver is rejecting the context attributes requested by Chrome, likely due to a regression in how Mesa 26-devel handles EGL context creation on the 7.0-rc5 kernel.

4. Compositor Frame Errors (Viz)
   Symptom: Visual corruption and check failures during frame production.
   Log Evidence:

Plaintext
[ERROR:cc/trees/layer_tree_host_impl.cc:1438] Check failed: viz_damage_rect.Contains(root_layer_damage_rect_).
Viz damage does not contain client damage! Client: 453,256 760x215 Viz: 452,261 762x211
Technical Analysis: This indicates a desync between the Chrome Renderer and the Viz Compositor, leading to incorrect "damage tracking" on Wayland.

Summary for Developers
The combination of Kernel 7.0-rc5 and Mesa 26-devel has introduced a breaking change in IPC (eventfd) and EGL context negotiation. This effectively disables all hardware acceleration paths (Vulkan, Graphite, and stable GL) for Chrome on Wayland for this hardware generation (Intel HD 5500).

Filing Instructions:
Chromium: File under Internals > GPU > Wayland. Mention that vm.memfd_noexec=0 did not resolve the issue.

CachyOS/Kernel: Highlight the eventfd and segfault in cosmic-workspaces, suggesting a wider IPC issue in the 7.0-rc5 build.

Mesa: Focus on the EGL_BAD_ATTRIBUTE failure when Chrome tries to discover the OpenGL adapter.

------------Alternative report---------------

🛠 Bug Report: GPU/Ozone Crash on Wayland (Kernel 7.0-rc)
Target: Chromium Issue Tracker / CachyOS Forums / Mesa GitLab

1. System Environment
   OS: CachyOS (Arch-based)

Kernel: 7.0.0-rc5-2-cachyos-rc

Browser: Google Chrome Canary 148.0.7760.0

Display Server: Wayland (Native)

Mesa Version: (OpenGL version string: 4.6 (Compatibility Profile) Mesa 26.1.0-devel (git-c0f1689e11)

Hardware: (Intel hd5500)

2. The Issue: "The Triple Failure"
   The browser fails to initialize a stable hardware-accelerated path when running natively on Wayland. This results in three distinct failure states:

Mojo IPC Crash: Enabling #mojo-use-eventfd causes an immediate Network Service crash/loop.

Ozone-Wayland Vulkan Conflict: Browser explicitly logs: '--ozone-platform=wayland' is not compatible with Vulkan.

Skia Graphite Block: Graphite is manually disallowed for "safety" on this platform.

3. Key Error Logs (Consolidated)
   Graphic Backend Rejection:
   [ERROR:gpu/config/gpu_finch_features.cc:645] : Enabling Graphite on a not-yet-supported platform is disallowed for safety
   [ERROR:ui/ozone/platform/wayland/gpu/wayland_surface_factory.cc:252] : '--ozone-platform=wayland' is not compatible with Vulkan.

EGL/Dawn Initialization Failure:
[ERROR:ui/gl/egl_util.cc:92] : EGL Driver message (Error) eglCreateContext: Requested version is not supported
Warning: eglCreateContext failed with EGL_BAD_ATTRIBUTE - While trying to discover a BackendType::OpenGL adapter.

Viz/Compositor Desync:
[ERROR:cc/trees/layer_tree_host_impl.cc:1438] : Check failed: viz_damage_rect.Contains(root_layer_damage_rect_). Viz damage does not contain client damage!

4. Steps to Reproduce
   Launch Chrome Canary on a Wayland session using Kernel 7.0-rc.

Set #ozone-platform-hint to Wayland.

Attempt to enable #enable-vulkan or #mojo-use-eventfd.

Observe the GPU process fallback to software or crash repeatedly.

5. Observed Regression
   Using --use-gl=angle --use-angle=gl still results in EGL_BAD_ATTRIBUTE, suggesting the EGL implementation in Mesa or the Ozone-Wayland bridge in Chromium is incompatible with the requested GL context versions on Kernel 7.0.
   about-gpu-2026-03-29T07-25-41-633Z.txt
   crash after enabling mojo (1).txt
   crash after enabling mojo (2).txt
   crash after enabling mojo (3).txt