On 2018.09.28 14:09:45 +0800, Zhang, Xiaolin wrote:
> On 09/27/2018 07:03 PM, Joonas Lahtinen wrote:
> > Quoting Xiaolin Zhang (2018-09-27 19:37:46)
> >> This int type module parameter is used to control the different
> >> level pvmmio feature for MMIO emulation in GVT.
> >>
> >> This parameter is default zero, no pvmmio feature enabled.
> >>
> >> Its permission type is 0400 which means user could only change its
> >> value through the cmdline, this is to prevent the dynamic modification
> >> during runtime which would break the pvmmio internal logic.
> >>
> >> Signed-off-by: Xiaolin Zhang <xiaolin.zhang@intel.com>
> > This shouldn't really be a module parameter. We should detect the
> > capability from the vGPU device and use it always when possible.
> >
> > Regards, Joonas
> >
> for pv optimization, we should touch both guest driver and GVTg.  this
> parameter is used for
> 
> guest pv capability because GVTg with pv capability will support both pv
> and non pv capability guest.
> 

That's the purpose of 'vgt_caps' in PVINFO to do capability check between
host/guest. You need a new cap bit definition for PVMMIO and maybe another
field for different PVMMIO level capability check. New parameter is not useful here.

Thanks

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