Affected Systems

Dell Latitude 7420: TPM Firmware Bug Causes 25-Second Boot Delay

Affected Systems:

Dell Latitude 7420 laptops running Linux kernel 5.16 or later

A firmware bug in the TPM (Trusted Platform Module) on Dell Latitude 7420 laptops is causing a 25-second boot delay when running Linux kernel 5.16 or later.

The bug affects the TPM_CRB msft0101 firmware and is not present in the kernel version 5.00 that came pre-installed on the Kubuntu distro shipped with the laptops.

The issue was reported on the Ubuntu Bug Tracker and is confirmed to affect other Linux distributions as well.

Dell has not yet released a fix for the bug, but the issue has been fixed in the next kernel update by hacking the i2c_hid_acpi.c

The only real fix for a problem like this is updating your UEFI and hope that the vendor fixed the bug.