rescan cpuid after ucode updates
After taking a microcode update we should be rescanning cpuid for a subset of features related to security and potentially adding them to the x86 feature set.
I tested this functionality in a few different ways:
First, I tested on systems that had microcode that was being updated early in boot which was what enabled additional features that should be rescanned (9746). I did this on a few different systems:
SMCI 1s Haswell
SMCI 2s Skylake
Next, to test the post ucodeadm path, I went through and removed the ucode upgrade file for a system and performed a microcode update with ucodeadm and made sure that it took.
I also tested on a system that did not have any microcode upgrade by the system to make sure that everything came up.
Most testing was all done on debug bits to catch cpuid pass assertions to make sure that we didn't mess anything up.
Updated by Electric Monk about 5 years ago
- Status changed from New to Closed
commit 01add34a714b536617e7bb35fa9dd6c1f4430827 Author: Robert Mustacchi <firstname.lastname@example.org> Date: 2018-09-11T02:31:02.000Z 9745 rescan cpuid after ucode updates 9746 Need cpuid detection for security sec features Reviewed by: John Levon <email@example.com> Reviewed by: Jerry Jelinek <firstname.lastname@example.org> Reviewed by: Andy Fiddaman <email@example.com> Reviewed by: Richard Lowe <firstname.lastname@example.org> Approved by: Dan McDonald <email@example.com>