ThinkPad T1g Gen 8 on Ubuntu 26.04: suspend resumes to black screen

I am seeing a suspend/resume issue on my laptop. When the system goes into suspend, it later comes back to a black screen. I cannot
recover the display normally and usually need to force reboot.

System information:

  • Laptop: Lenovo ThinkPad T1g Gen 8
  • Machine type: 21TD000MUS
  • Ubuntu: 26.04 (Resolute Raccoon, development branch)
  • Kernel: 7.0.0-10-generic
  • CPU: Intel Core Ultra 9 285H

Graphics:

  • Intel integrated GPU: Intel Arrow Lake-P [Arc Pro 130T/140T]
  • NVIDIA discrete GPU: GeForce RTX 5070 Max-Q / Mobile
  • NVIDIA driver: 595.58.03

Suspend-related details:

  • /sys/power/mem_sleep shows only: [s2idle]
  • Kernel log says: “Low-power S0 idle used by default for system suspend”

Relevant observations:

  • I can see suspend handling starting in the logs, for example:
    • “rtkit-daemon: Handling system-suspend using logind.”
  • But I do not see a clean resume sequence afterward.
  • This matches the actual behavior: after suspend, the machine returns to a black screen and I often need to hard reboot.

There are also NVIDIA-related messages in the logs, including:

  • “nvidia-modeset: WARNING: GPU:0: Correcting number of heads for current head configuration”
  • “nvidia … [drm] No compatible format found”
  • “nvidia … [drm] Cannot find any crtc or sizes”

uname -a:
Linux yangshirong 7.0.0-10-generic #10-Ubuntu SMP PREEMPT_DYNAMIC Thu Mar 19 10:24:42 UTC 2026 x86_64 GNU/Linux

lsb_release -a:
Distributor ID: Ubuntu
Description: Ubuntu Resolute Raccoon (development branch)
Release: 26.04
Codename: resolute

lspci | grep -Ei ‘vga|3d|display’:
00:02.0 VGA compatible controller: Intel Corporation Arrow Lake-P [Arc Pro 130T/140T] (rev 03)
01:00.0 VGA compatible controller: NVIDIA Corporation GB206M [GeForce RTX 5070 Max-Q / Mobile] (rev a1)

nvidia-smi:
Driver Version: 595.58.03
CUDA Version: 13.2