Re: [PATCH v5 06/17] virt: acrn: Introduce VM management interfaces

[Greg Kroah-Hartman]

On Thu, Nov 05, 2020 at 08:48:22PM +0800, Shuo A Liu wrote:
> > > > > Though i can
> > > > > keep some reserved fields for alignment (and to keep same data structure
> > > > > layout with the hypervisor), right?
> > > > > Documentation/driver-api/ioctl.rst says that explicit reserved fields
> > > > > could be used.
> > > >
> > > > If you need alignment, yes, that is fine, but that's not what you are
> > > > saying these are for.  And if you need alignment, why not move things
> > > > around so they are properly aligned.
> > > >
> > > > And this structure has nothing to do with the hypervisor structure,
> > > > that's a internal-kernel structure, not a userspace-visable thing if you
> > > > are doing things correctly.
> > > 
> > > It's the same structure with the one in hypervisor. HSM driver
> > > doesn't maintain the VM much, it just pass the data for VM creation from
> > > userspace to hypervisor.
> > 
> > That sounds ripe for abuse, good luck!
> 
> The hypervisor will do the sanity check. In this case, HSM driver can be
> kept simple.

Hah, good luck with the fuzzers, crashing a hypervisor will be fun for
them!

greg k-h