On Thu, Mar 31, 2011 at 06:03:37AM -0400, Avi Kivity wrote:
> On 03/31/2011 11:42 AM, Roedel, Joerg wrote:
> > On Thu, Mar 31, 2011 at 05:18:28AM -0400, Avi Kivity wrote:
> > > On 03/31/2011 09:14 AM, Roedel, Joerg wrote:
> > > > On Mon, Mar 28, 2011 at 08:28:12AM -0400, Avi Kivity wrote:
> > > > > The spec indicates we need to check the TSS and IOPL based
> > > permissions
> > > > > before the intercept (vmx agrees). With the code as is, it
> > > happens
> > > > > afterwards.
> > > > >
> > > > > One way to do this is to have an ExtraChecks bit in the
> > > opcode::flags.
> > > > > Then opcode::u.xcheck->perms() is the pre-intercept check and
> > > > > opcode::u.xcheck->execute() is the post-intercept execution.
> > > Should
> > > > > work for monitor/mwait/rdtsc(p)/rdpmc/other crap x86 throws at us.
> > > >
> > > > Okay, as you suggested, I put these checks into the instruction
> > > emulator
> > > > and let the hard work of implementing per-arch checks to the
> > > nested-vmx
> > > > people ;)
> > > > I doubt that this makes the opcode-tables more readable, but lets see
> > > :)
> > >
> > > I think we're miscommunicating. I'm talking about x86 checks, not virt
> > > vendor specific checks.
> >
> > The place of the intercept check may be vendor specific. I havn't looked
> > at the Intel spec, though. But there are probably differences.
>
> That's why there are three hooks: pre-ex, post-ex, post-mem. If an
> intercept fits in between, use the pre-ex hook and duplicate the checks
> in the intercept.
>
> As far as I recall, everything should fit into those three, though.
Okay, thats the way to go then, thanks.
Joerg
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