Qubes OS 4.1: i3 Blurred Graphics on T450s

2022-01-19

How To Fix Blurred Intel Integrated Graphics on a ThinkPad T450s running Qubes OS 4.1 and i3 Window Manager

What is Qubes OS?

Qubes OS, the reasonably secure operating system is a great OS that I’ve been using as my daily driver for quite some time now. It’s designed as a single-user, security focused OS and can be best described as a “Xen Operating System” that uses the mighty Xen type-1 (baremetal) hypervisor to allow for multiple operating systems called “qubes” to run on your computer simultaneously.

It’s a great way to learn more about Xen virtualization while giving you peace of mind when it comes to your operational security. Reasonable peace of mind that is, especially when used in combination with a Coreboot box. Anyway, I should probably write about Qubes OS more but let’s get back to topic:

Upgrading to Qubes OS 4.1.0-rc3

I recently upgrade from Qubes OS stable release 4.0.4 to 4.1.0-rc3, which was a great move as the new release comes with plenty of improvements that you can read about in the Release Notes.

For me, some of the highlights of the new release includes:

Xen version 4.14, better protection against privilege escalation attacks
choice of running all qubes as Debian 11 in the installer
sys-firewall and sys-usb are now disposable qubes
better performance and less RAM intense operation
suspend and hibernate works out of the box

Installation was really smooth, the overall performance has improved significantly and it’s great to be able to suspend/hibernate without having to fiddle around with kernel boot parameters to get (maybe) get it working. So far no downside, and the systems if stable and ready for production IMHO.

Blurred Graphics when using i3 Window Manager

Except for this one little issue that I needed to fix:

When using i3, which I so much prefer to the default Qubes WM that is the Xfce Desktop Environment that I can’t live without it, I experienced slightly blurred graphics. This was probably caused by slow software rendering due to the integrated Intel graphic card on my ThinkPad T450s.

How To Fix It

Luckily - and thanks to the Qubes Community there’s a pretty simple workaround to fix this:

From within dom0, you’d go edit /etc/default/grub and within the GRUB_CMDLINE_LINUX= you replace the i915.alpha_support=1 with i915.force_probe=* or add it accordingly.
Within the line GRUB_CMDLINE_XEN_DEFAULT= you add the setting iommu=no-igfx
Rebuild your grub config by doing a sudo grub2-mkconfig --output /boot/grub2/grub.cfg

Proceed to create the file /etc/X11/xorg.conf.d/20-intel.conf as root and within dom0, and fill it with:

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Section "Device"
        Identifier "Intel Graphics"
        Driver "Intel"
EndSection

Reboot your box and voilà your i3 window manager on Qubes OS 4.1 should be good to go.

:wq

#QubesOS #i3