Issue with "Suspend" on Lenovo T560 - cannot wake up from "deep"

Support and Help
1

Ubuntu Version: 24.04.2 Desktop

Desktop Environment: GNOME (standard desktop install)

Problem Description: Cannot wake laptop after “Suspend”. The typical Lenovo Thinkpad “soft blink” of the power button LED and the red LED on the lid just continues.

Relevant System Information:
Lenovo T560, Intel i7-6600U, 16 GB ram, built-in graphics, built-in monitor.
No peripherals attached; no usb sticks connected, no external mouse/keyboard, …

What I’ve Tried:
I have updated BIOS to the latest available from Lenovo (1.45).
Searched for “sleep mode” option in BIOS, but there is none. I tried to disable “Secure Boot” in BIOS which is allegedly sometimes fixing the issue, but it did not help.

Using

cat /sys/power/mem_sleep

I established that the Kernel was using [deep] out of the box. Defining a kernel parameter for s2idle in /etc/default/grub

GRUB_CMDLINE_LINUX_DEFAULT=“quiet splash mem_sleep_default=s2idle”

helped, but I don’t like that solution: The power saving is not as much as for “deep”, and the Power Button LED does not indicate “sleep”; it stays as lit as when the computer is on, so one cannot check/know if the PC is sleeping or if the screen is just turned off.

TLP is not running in Ubuntu, so the recommendation found elsewhere to try to disable TLP is not relevant.

Is there any other kernel parameters or tweaks that could make “deep” sleep work on my T560? It was working with Win10.

3

Ubuntu Version:
24.04.2 Desktop

Desktop Environment (if applicable):
GNOME (standard desktop install)

Problem Description:
Cannot wake laptop after “Suspend”. Reference is made to ole post with (almost) same title.

Relevant System Information:
Lenovo T560, Intel i7-6600U, 16 GB ram, built-in graphics, built-in monitor.
No peripherals attached; no usb sticks connected, no external mouse/keyboard

SOLVED:
Could not re-open previous message to post the solution - for anyone having the issue and finding my previous post.

Make sure to disable virtualization in BIOS: I set both VT‑x and VT‑d to disabled in BIOS (under Security → Virtualization or Config → CPU) and then the suspend works for my good old T560. Perhaps it is sufficient to just disable Intel VT‑d (IOMMU) - the advanced feature for PCI device passthrough (I didn’t test).

This solution is OK for me because I only plan to use the laptop for “plain desktop work” (no plan to run Windows, or another Linux or an entirely different OS in VirtualBox/VMware/QEMU).