MDS/SSB Mitigation for pre-Nehalem/Older Intel Hardware?

[Zdenek Kaspar]

Hello everyone,

on old CPU the current situation looks like this:

l1tf:Mitigation: PTE Inversion; VMX: EPT disabled
mds:Vulnerable: Clear CPU buffers attempted, no microcode; SMT disabled
meltdown:Mitigation: PTI
spec_store_bypass:Vulnerable
spectre_v1:Mitigation: __user pointer sanitization
spectre_v2:Mitigation: Full generic retpoline, STIBP: disabled, RSB filling

There's no way to mitigate some issues without microcode
and Intel doesn't provide new updates for old hardware.

The Deep Dive document for MDS includes: "software sequences
to overwrite buffers" but it goes back only to Nehalem.

Are there any plans for software fixes especially for older CPUs?

TIA, Z.