Hardware:

Lenovo ThinkPad X1 Carbon 5th gen (system-product-name: 20HRCTO1WW)
Intel Kaby Lake-U GT2 [HD Graphics 620], PCI ID [8086:5916] (rev 02)
Intel Wireless-AC 8265

Bisect result:

7.0.0-27.27 (resolute-security): resumes from suspend correctly, every time, 
tested across multiple suspend/resume cycles
7.0.0-28.28 (resolute-updates): fails to resume every time — screen stays 
black, system otherwise alive (keyboard backlight/fan resume, Caps Lock LED 
responds to keypresses), no recovery via VT switch (Ctrl+Alt+F3 → F1)

Suspend/resume logs (7.0.0-28.28, failing case):
journalctl shows a clean cycle with no errors around resume:
PM: suspend entry (deep)
...
ACPI: PM: Low-level resume complete
PM: suspend exit
No i915/DRM errors logged. mem_sleep is set to deep (S3, not s2idle).
Already ruled out:

i915.enable_dc=0 kernel param — no effect on the failure

Additional context:
7.0.0-28.28 has at least one other confirmed regression (amdgpu/ROCm 
performance, unrelated to this i915 issue), acknowledged by the Ubuntu Kernel 
Team on 2026-07-16 and shipped anyway to carry urgent security fixes: 
https://discourse.ubuntu.com/t/amdgpu-performance-regression-in-kernel-7-0-0-28-28/85237.
 Flagging in case this build warrants broader regression review.
Happy to test any diagnostic kernel params or provide further logs — currently 
running 7.0.0-27.27 as a workaround (held via apt-mark).

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2161243

Title:
  System fails to resume from suspend (black screen) on kernel
  7.0.0-28-generic; works correctly on 7.0.0-27-generic

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2161243/+subscriptions


-- 
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to