[Mac] Secondary Lighting above Fair hangs the GPU on Enter World and reboots the Mac (M5 Pro, macOS 26.5.2)

In Development WoW: Forever Beta Discussion
1

Build: WoW: Forever Beta 1.60.1.69913, Mac arm64, Metal (mtl_1_1). Same result with Enhanced and Classic models.
Hardware: MacBook Pro 16" M5 Pro (Mac17,8), 48 GB, macOS 26.5.2 (25F84), built-in display 1728x1117 @ 120 Hz.
Settings: fresh install, auto-detected Graphics Quality 6, which sets Secondary Lighting to High (graphicsLightMode 2, giQuality 3), render scale 50%.

Steps

  1. Log in, create a character, Enter World.
  2. Loading bar reaches 100%, the intro cinematic starts with audio only, the display stays frozen on the loading screen.
  3. WindowServer stops checking in, watchdogd kills it (the client is terminated with SIGTERM [HANG] in Errors/), it hangs again right away, and after the second induced crash within 120 seconds the kernel panics and the Mac reboots. Reproduced three times in a row this morning, two of them ending in a reboot.

Evidence (from /Library/Logs/DiagnosticReports)

Both panic reports carry the same string:

panic(cpu 5 caller 0xfffffe004f8a1e44): userspace watchdog timeout: no successful checkins from WindowServer (2 induced crashes) in 120 seconds
WindowServer has not exited since first loaded
service: WindowServer (2 induced crashes), total successful checkins in 660 seconds: 54, last successful checkin: 120 seconds ago

WindowServer watchdog stackshot (userspace_watchdog_timeout.spin), main thread, identical for all 12 samples:

Thread "ws_main_thread"  DispatchQueue "com.apple.SkyLight.mtl_submit"
  SkyLight -> Metal -> libdispatch -> Metal -> IOGPU -> IOKit
  -> kernel: IOGPUFamily -> AGXG17X -> IOGPUFamily (never returns)

The GPU command stream is stuck inside the AGX driver and WindowServer never gets its frame back. The trigger is the Secondary Lighting setting: with it at High the GPU hangs at Enter World every time; with it at Fair and every other setting unchanged the game runs.

Workaround (verified)

Set Secondary Lighting to Fair before entering the world (System > Graphics at the character screen), or with the game closed in WTF/Config.wtf:

SET graphicsLightMode "0"
SET raidGraphicsLightMode "0"
SET giQuality "1"
SET RAIDgiQuality "1"

Everything else stayed at preset 6 (shadows 3, SSAO 3, sunshafts 2, reflections 2). 77 minutes in the world afterwards with no hang and no new watchdog or panic reports.

For reference, the Secondary Lighting dropdown in the Forever UI (Blizzard_SettingsDefinitions_Shared/Graphics.lua, gated by C_VideoOptions.IsSecondaryLightingSupported()) maps 0 = Fair, 1 = Good, 2 = High to graphicsLightMode; the engine CVar is giQuality (1 to 3), and giQuality 0 asserts, so GI cannot be disabled outright.

This is the same failure reported in “Mac client crashing wow: forever”, “Forever - Beta” (Mac Technical Support) and “Mac Crashing Solution! Turn SECONDARY LIGHTING to FAIR”, and it is not in the September 17 known issues list. Until the Metal GI pass is fixed, capping Secondary Lighting at Fair in the Mac auto-detect would stop the reboots.

19 Likes
[Mac] 8 different graphics bugs, each isolated to one setting — with repro steps for each
2

wtf is this. steve jobs told me it just werks

1 Like
3

Confirmed it is only this setting - while the lighting in general looks bad with darkened objects and washed out colors, even running at 10 on an m5 will work if you just lower that one setting back to fair.

1 Like
4

Did you happen to find a solution for the The entire UX being Tinted Green and all Water and Plant Life being Basically Black Pools of Ink?

2 Likes
5

MBP M4 Max running Tahoe 26.7.1. Just confirming leaving all graphic settings at auto-detected level 6, and changing Secondary Lighting to Fair fixed my game crashing issues.

1 Like
6

Set shadows quality to low. Any other setting sets foliage to true black 0,0,0.

I go over it and other bugs here.

3 Likes
7

For me Turning Shadows and Secondary Lighting all the way down sort of fixed it. Although I still get weird shadows in massive squares, the game is at least mostly playable. It also fixed the inky water/plants and the green filter. Thats on a Mac Mini M4

8

I go over all of these too:

Setting enabled / raised Symptom
Triple Buffering Colour corruption that accumulates frame over frame
Advanced Work Submit Colour corruption (“leak”) — independently, with Triple Buffering already off
Optional GPU Features Hard horizontal bands across trunks and walls
Secondary Lighting above Fair Crash / kernel panic (this post’s finding — confirmed)
Shadow Quality above Low Shadows render pure black, measured 0,0,0
1 Like
9

This work around fix works until it doesn’t. Even with it on fair for secondary lighting and everything cranked down to 1 I can get this to hard crash the system via the same WindowServer panic while trying to log into my toon who is trying to load into Deep Run Tram. A toon I played on with this work around until level 14. Hard rebooted the Mac Studio (M2 Ultra, 64GB RAM) 4 times and ensured everything was cranked down (which had worked before). Still goes into a panic and forces a hard reset to recover the system.

So there is a work around until it breaks somewhere else in the world.

2 Likes
11

My character has been stuck in the deep run tram all day. Tried to travel from SW to IF. No matter what graphics setting I put , even the lowest, on my Mac , loading in just crashes my entire Mac

Such a bummer

2 Likes
12

Same issue. Practically the same hardware. Unfortunately, I only get an hour in the evening right now because I am working 13 hour shifts. I was hoping it would have been fixed by this evening.

13

Same issue on Debian Linux with Nvidia’s 615 driver and the latest Proton GE through Steam. I played on my Gnome priest the first day, logged off and on a few times successfully. I figured I would try to go to Stormwind through the deeprun tram and when I hopped into the Stormwind portal my game crashed. Now if I try to login on that character I get the same issue as the original poster: Loading bar goes to full, then my game freezes and eventually crashes. I made a new character: A Human rogue and logged off in Northwind for the night. When I try to login today it does the same as with my Gnome.

Making a new character works. I’ve tried setting my lighting to fair and launching the game with direct 3D 11 renderer, and all lowest settings, but I can’t get in unless I make a new character. Glad this is already reported, thought I would add my 2 cents.

14

Its not just Mac, it causes issues for AMD GPU Windows builds.

15

Thank you, this helped me get the game to work on an M4 Max Mac Studio. I turned the shadow quality to low and got rid of a weird green overlay bug

16

Yeah, I haven’t tried it on my Mac yet, but on my gaming tower with an RX 9070, every time I launch the beta the graphics driver has to hard crash once before it’ll let me play.

It seems like non-Nvidia GPUs haven’t gotten a lot of attention.

17

Also one of my guys had green overlay bug fixed when he chose Auto in his graphical adapter settings from the specific one (although there’s still another bug with shadow beyond low, which causes a lot of stuff to just be black)

18

Changing the Shadow Quality setting to Low fixed this issue for me :slight_smile:

19

Changing Shadow Quality to Low fixed that issue for me :slight_smile: