Re: [PATCH 15/17] KVM: retpolines: x86: eliminate retpoline from vmx.c exit handlers

Sean Christopherson
2019-09-24T00:35:02Z

On Tue, Sep 24, 2019 at 02:16:36AM +0200, Paolo Bonzini wrote:
> On 23/09/19 23:08, Andrea Arcangeli wrote:
> > The two most attractive options to me remains what I already have
> > implemented under #ifdef CONFIG_RETPOLINE with direct calls
> > (optionally replacing the "if" with a small "switch" still under
> > CONFIG_RETPOLINE if we give up the prioritization of the checks), or
> > the replacement of kvm_vmx_exit_handlers with a switch() as suggested
> > by Vitaly which would cleanup some code.
> >
> > The intermediate solution that makes "const" work, has the cons of
> > forcing to parse EXIT_REASON_VMCLEAR and the other vmx exit reasons
> > twice, first through a pointer to function (or another if or switch
> > statement) then with a second switch() statement.
>
> I agree. I think the way Andrea did it in his patch may not the nicest
> but is (a bit surprisingly) the easiest and most maintainable.

Heh, which patch? The original patch of special casing the high
priority exits?