Phillip Whittlesea-Clark

Software Architect & Dungeon Master

1 minute read

Last week I upgraded my ever-reliable Lenovo x260 ThinkPad to Ubuntu 24.04.

Somewhere in the hour long install process the installer asked me to replace my /etc/default/grub file with the default one in the installer.

I didn’t remember updating this file, ever, so I accepted the defaults.

Isn’t Ubuntu wonderful, I thought, major version updates are so smooth! However, little did I know, that due to a little documented issue I would not be able to wake my laptop from a suspend state anymore.

When I close the lid, my laptop sleeps, never to be woken from its slumber; stirred only by the harsh application of a long-press of the power button to hard reset it.

My first guess at a cause was a bad upgrade, so I installed a fresh copy of 24.04, which yielded no love.

After a suspicion my hardware was no longer supported, I reinstalled 22.04 to little joy.

Maybe it was the boot drive encryption I dutifully enabled? No such luck.

After 3 fresh installs I scoured forums, until I came across a comment on the issue above:

Simon Clift (ssclift-gmail) wrote 21 hours ago: #27

I’m not sure exactly why, but this worked:

https://www.reddit.com/r/debian/comments/t03sd2/fresh_install_on_t460_laptop_wont_wake_after/

Change the /etc/default/grub command line to

GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash intel_iommu=off”

and my Thinkpad Carbon X1 (G4?) sleeps and wakes up as expected. I experienced the problem of not waking up after sleep on Ubuntu 22.04 and 24.04.

This rang a bell, had I changed this file before? Maybe?

Anyway, a quick edit of my grub config file later and success! My ThinkPad is usable again!

Thanks Simon Clift, wherever you are!

# Added this in to help with not being able to resume from suspend
# https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2031969/comments/27
# Run sudo update-grub after!
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash intel_iommu=off"