Comment 4 for bug 1921880

The initial request lists quite some changes already, but there might
be more needed to fully round this up and get it working smoothly.
At least as long as we consider this back to the last LTS being Focal
the following changes are missing as well:

Libvirt
for amd-stibp
1921880 v6.5.0 892b7c70 cpu_map: Add missing x86 features in 0x80000008 CPUID leaf
For npt and others
1921880 v6.5.0 96a39aad cpu_map: Add missing AMD SVM features
For rdpid
1921880 v6.5.0 6ea3bb19 cpu_map: Add missing x86 features in 0x7 CPUID leaf

Qemu:
For STIBP (AMD) and many others
1921880 v5.0.0 143c30d4 i386: Add 2nd Generation AMD EPYC processors
For FSRM
1921880 v5.1.0 5cb287d2 target/i386: add fast short REP MOV support
For svm_addr_chk and others
1921880 v6.5.0 96a39aad cpu_map: Add missing AMD SVM features