I'm currently running Ubuntu 24.04.1 with Full Disk Encryption (FDE) and TPM integration. I’m looking to update the kernel cmdline to try to work around an issue with Intel i915 that’s causing screen freezing and flickering.

Relevant bug reports for reference:

https://bugs.launchpad.net/ubuntu/+s...x/+bug/2062951
https://bugs.launchpad.net/ubuntu/+s...5/+bug/2049027

To resolve this, I tried adding intel_iommu=igfx_off to the cmdline with these commands:

Code:
$ sudo snap set system system.kernel.dangerous-cmdline-append="intel_iommu=igfx_off"
$ sudo snap get system system.kernel.dangerous-cmdline-append
intel_iommu=igfx_off
After rebooting, however, the cmdline doesn’t show the parameter as expected:

Code:
$ cat /proc/cmdline 
snapd_recovery_mode=run console=ttyS0,115200n8 console=tty1 panic=-1 quiet splash