Laptop freeze 3 times in 1h, how to diagnose?

Still no luck, there are again freezes with associated errors of i915:

Mai 02 22:55:04 Kiwi kernel: i915 0000:00:02.0: [drm] *ERROR* GT0: rcs0 reset request timed out: {request: 00000001, RESET_CTL: 00000001}
Mai 02 22:55:19 Kiwi kernel: BUG: kernel NULL pointer dereference, address: 0000000000000278
Mai 02 22:55:19 Kiwi kernel: #PF: supervisor read access in kernel mode
Mai 02 22:55:19 Kiwi kernel: #PF: error_code(0x0000) - not-present page
-- Boot 0ca0e5bf26a749dfb3c1646cf50c910a --

By now I have:

  • switched back to Wayland instead of Xorg (supposedly more "graceful" error-handling)
  • i915.enable_psr=0 (disable PSR, power save mode, as suggested by @sammolaw)
  • deactivated hardware acceleration for Brave

After some suggestions by ChatGPT4/turbo I also tried disable power save mode rc6 of GPU (i915.enable_rc6=0), but this does not seem to work because apparently this is not configurable in the current kernel 6.8.0-58-generic.

If I remember correctly the freezes started with some of the updates approximately two weeks ago. There was a kernel update at the time, is it possible that this is related? Should I try a downgrade to the older version of the kernel?