From Fedora Project Wiki

Description

This test case tests that a system continues to work correctly with updated processor microcode from the microcode_ctl package.

Test on real Intel systems only
Processor microcode updates usually apply only to real systems (not virtual machines). The microcode_ctl package only handles microcode updates for Intel processors. Thus it is only useful to run this test on a real system with an Intel processor.
Note processor model when reporting results
When reporting results for this test, include a comment noting your exact processor model. If you do not know, you can run cat /proc/cpuinfo to find out.

Setup

  1. Ensure you have at least two working kernels installed, for recovery purposes.
  2. Check which kernel is currently running, with uname -r.

How to test

  1. Apply the microcode_ctl package update you wish to test.
  2. Run sudo dracut -f to re-generate the initramfs for the currently-running kernel. If you would rather test with a different kernel from the one you are currently running, you can specify a kernel version with sudo dracut -f --kver (version).
  3. Reboot the system and boot the appropriate kernel: the same one you were running before, if you just ran dracut -f.
  4. Check that the system boots and functions correctly. If it does not, boot with a different kernel, downgrade the microcode_ctl package to the previous version, and use dracut -f --kver (version) to re-generate the initramfs for the affected kernel, so it will boot correctly again.

Expected Results

  1. The system should boot and function correctly with the updated microcode:
$ dmesg | grep microcode:
[    1.904383] microcode: Current revision: 0x00004122
[    1.904386] microcode: Updated early from: 0x00004121