Re: [PATCH v2] KVM: VMX: Update instruction length on intercepted BP

Gleb Natapov
2010-02-17T11:16:49Z

On Wed, Feb 17, 2010 at 01:13:29PM +0200, Avi Kivity wrote:
> On 02/17/2010 12:43 PM, Gleb Natapov wrote:
> >>And, again: This is an _existing_ user space ABI. We could only provide
> >>an alternative, but we have to maintain what is there at least for some
> >>longer grace period.
> >>
> >But it was always broken for SVM and was broken for VMX for a year and
> >nobody noticed, so may be instead of reintroducing old interface we should
> >do it right this time?
>
> We need to fix the existing interface first, and then think long and
> hard if we want yet another interface, since we're likely to screw
> it up as well.
>
> The more interfaces we introduce, the harder maintenance becomes.
>
We are in a sad state if we cannot improve interface. The current one
outsource part of CPU functionality into userspace. This should be a big
no-no.

--
Gleb.