> On Fri, Jan 05, 2018 at 04:37:30PM +0000, David Woodhouse wrote: > > You are completely ignoring pre-Skylake here. > > > > On pre-Skylake, retpoline is perfectly sufficient and it's a *lot* > > faster than the IBRS option which is almost prohibitively slow. > > > > We didn't do it just for fun. And it's working fine; it isn't *that* > > complex. > > How do you enable IBRS when the CPU switches to SMM?
you do not need to. SMM takes care of itself.