Re: [RFC v2 08/32] x86/traps: Add #VE support for TDX guest

[Andy Lutomirski]

On Tue, Jun 8, 2021, at 11:15 AM, Dave Hansen wrote:
> On 6/8/21 11:12 AM, Andi Kleen wrote:
> > I believe neither does mmio/msr normally (except maybe
> > ftrace+tp_printk, but that will likely work because it shouldn't
> > recurse more than once due to ftrace's reentry protection)
> 
> Can it do MMIO:
> 
> > +DEFINE_IDTENTRY(exc_virtualization_exception)
> > +{
> =======> HERE
> > +    ret = tdg_get_ve_info(&ve); 
> 
> Recursion isn't the problem.  It would double-fault there, right?
> 

We should do the get_ve_info in a noinstr region.