Laptop12 w/ KUbuntu 25.04 freezing when suspending

Just an update on this, in case anyone had the same issue and happened on this thread.
I did some investigation and I’m trying a few scenarios:

  1. Change the type of sleep, default seems to be s2idle which is quicker because memory isn’t put to sleep - which also explains the higher than expected battery usage - @Ivirono
    I tried changing this, but it didn’t seem to fix the issue. I might keep it anyway, to save battery.

Here are the steps:

  • To check the status: cat /sys/power/mem_sleep
    Which in my case was showing [s2idle] deep
  • To force deep, if supported:
sudo bash -c 'echo deep > /sys/power/mem_sleep'
systemctl suspend

  • To make it permanent, add it to /etc/default/grub:
GRUB_CMDLINE_LINUX_DEFAULT="... mem_sleep_default=deep"

  • and then sudo update-grub
  1. I’m now working on the new systemd 257, which seems to have reported issues when suspending. First test is about bypassing systemd’s suspend logic and leave it to the kernel to handle it:
  • add this to /etc/systemd/sleep.conf
[Sleep]
SuspendMode=platform 
  • and reload: sudo systemctl daemon-reexec

I tested this only a couple of days, but it seems to be promising.