Re: [PATCH v2 4/7] x86/vmx: add do_vmtrace_op

[Roger Pau Monné <roger.pau@xxxxxxxxxx>]

On Mon, Jun 22, 2020 at 06:16:57PM +0200, Jan Beulich wrote:
> On 22.06.2020 18:02, Michał Leszczyński wrote:
> > ----- 22 cze 2020 o 17:22, Jan Beulich jbeulich@xxxxxxxx napisał(a):
> >> On 22.06.2020 16:35, Michał Leszczyński wrote:
> >>> ----- 22 cze 2020 o 15:25, Jan Beulich jbeulich@xxxxxxxx napisał(a):
> > It's also not "many gigabytes". In most use cases a buffer of 16/32/64 MB
> > would suffice, I think.
> 
> But that one such buffer per vCPU, isn't it? Plus these buffers
> need to be physically contiguous, which is an additional possibly
> severe constraint.

FTR, from my reading of the SDM you can use a mode called ToPA where
the buffer is some kind of linked list of tables that map to output
regions. That would be nice, but IMO it should be implemented in a
next iteration after the basic support is in.

Roger.