RE: [PATCH v2 4/8] x86/spec_ctrl: Add sysctl knobs to enable/disable SPEC_CTRL feature

[Van De Ven, Arjan]

> > it's a mistake though... retpoline is what people should be using ....
> > ... and only in super exception cases should IBRS even be considered
> 
> Like on certain Skylake and Broadwell where using the retpoline won't suffice?

skylake is a bit more complex but that was discussed in earlier emails where a few more things are needed. No idea what you're inventing on broadwell where you would use ibrs but not retpoline


>  - The CPU can do retpoline, but MSRS are faster (is that even the case?)

that is never the case