Re: [PATCH v2 01/12] viridian: don't blindly write to 32-bit registers is 'mode' is invalid

[Jan Beulich <jbeulich@xxxxxxxx>]

On 20.11.2020 10:48, Paul Durrant wrote:
> From: Paul Durrant <pdurrant@xxxxxxxxxx>
> 
> If hvm_guest_x86_mode() returns something other than 8 or 4 then
> viridian_hypercall() will return immediately but, on the way out, will write
> back status as if 'mode' was 4. This patch simply makes it leave the registers
> alone.

IOW 16-bit protected mode and real mode aren't allowed to make
hypercalls (supported also be the earlier switch() in the
function)? But then, to achieve what you want, wouldn't it be
more direct to simply "return HVM_HCALL_completed;" straight
from that earlier switch()'s default case? At which point the
switch() you modify could become if/else? Anyway - you're the
maintainer, I'm just wondering ...

Jan