Re: [kvm-unit-tests PATCH v3 1/3] s390x: pv: implement routine to share/unshare memory

[Claudio Imbrenda <imbrenda@linux.ibm.com>]

On Wed, 20 Jan 2021 11:48:52 +0100
Thomas Huth <thuth@redhat.com> wrote:


[...]

> > +/*
> > + * Guest 2 request to the Ultravisor to make a page shared with the
> > + * hypervisor for IO.
> > + *
> > + * @addr: Real or absolute address of the page to be shared  
> 
> When is it real, and when is it absolute?

as far as we are concerned, it's unpredictable

this means that a guest should avoid sharing any prefix (or
reverse prefix) pages.

> > + */
> > +static inline int uv_set_shared(unsigned long addr)
> > +{
> > +	return share(addr, UVC_CMD_SET_SHARED_ACCESS);
> > +}
> > +
> > +/*
> > + * Guest 2 request to the Ultravisor to make a page unshared.
> > + *
> > + * @addr: Real or absolute address of the page to be unshared  
> 
> dito

same

> > + */
> > +static inline int uv_remove_shared(unsigned long addr)
> > +{
> > +	return share(addr, UVC_CMD_REMOVE_SHARED_ACCESS);
> > +}
> > +
> >   #endif  
> 
> Apart from the nits:
> Acked-by: Thomas Huth <thuth@redhat.com>
>