Re: [PATCH v2 2/2] x86/dom0: attempt to fixup p2m page-faults for PVH dom0

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

On Tue, Feb 18, 2025 at 04:58:20PM +0100, Jan Beulich wrote:
> On 18.02.2025 16:44, Roger Pau Monné wrote:
> > On Tue, Feb 18, 2025 at 03:35:04PM +0100, Roger Pau Monne wrote:
> >> --- a/docs/misc/xen-command-line.pandoc
> >> +++ b/docs/misc/xen-command-line.pandoc
> >> @@ -822,7 +822,8 @@ Specify the bit width of the DMA heap.
> >>  
> >>  ### dom0
> >>      = List of [ pv | pvh, shadow=<bool>, verbose=<bool>,
> >> -                cpuid-faulting=<bool>, msr-relaxed=<bool> ] (x86)
> >> +                cpuid-faulting=<bool>, msr-relaxed=<bool>,
> >> +                pf-fixup=<bool> ] (x86)
> >>  
> >>      = List of [ sve=<integer> ] (Arm64)
> >>  
> >> @@ -883,6 +884,19 @@ Controls for how dom0 is constructed on x86 systems.
> >>  
> >>      If using this option is necessary to fix an issue, please report a 
> >> bug.
> >>  
> >> +*   The `pf-fixup` boolean is only applicable when using a PVH dom0 and
> >> +    defaults to false.
> > 
> > I'm considering whether the default should instead be true, so that
> > PVH is closer to what which regions a classic PV dom0 gets access to.
> 
> I was wondering about this too, but then thought that we may want to do
> this in a separate step, once we've had some more coverage.

Ack, let's put it in first and consider changing the default later.

Thanks, Roger.