Re: [PATCH v3 2/2] tools: set event channel HVM parameters in libxenguest

[Anthony PERARD <anthony.perard@xxxxxxxxxx>]

On Wed, Dec 08, 2021 at 04:02:17PM +0000, Andrew Cooper wrote:
> On 08/12/2021 15:57, Juergen Gross wrote:
> > On 08.12.21 16:54, Andrew Cooper wrote:
> >> On 08/12/2021 14:22, Juergen Gross wrote:
> >>> On 08.12.21 14:43, Andrew Cooper wrote:
> >>>> On 08/12/2021 08:47, Juergen Gross wrote:
> >>>>> The HVM parameters for pre-allocated event channels should be set in
> >>>>> libxenguest, like it is done for PV guests and for the pre-allocated
> >>>>> ring pages.
> >>>>>
> >>>>> Suggested-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> >>>>> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> >>>>
> >>>> I'm not sure that we have the concept of pre-allocated ring pages.
> >>>>
> >>>> For PV, we have:
> >>>>
> >>>>       dom->console_pfn = xc_dom_alloc_page(dom, "console");
> >>>>       if ( dom->console_pfn == INVALID_PFN )
> >>>>           return -1;
> >>>>       xc_clear_domain_page(dom->xch, dom->guest_domid,
> >>>>                            xc_dom_p2m(dom, dom->console_pfn));
> >>>>
> >>>> and for HVM, we have:
> >>>>
> >>>>       dom->console_pfn = special_pfn(SPECIALPAGE_CONSOLE);
> >>>>       xc_clear_domain_page(dom->xch, dom->guest_domid,
> >>>> dom->console_pfn);
> >>>
> >>> Isn't that a pre-allocation? The PFNs are fixed at boot time of the
> >>> guest.
> >>
> >> Yeah, but "allocated in the library call we're making" is not the same
> >> as "caller has to allocate and pass details in".
> >>
> >> I would not class the frames as "pre-allocated" in this context.
> >> "allocated" sure, so perhaps "just like it is done for PV guests, and
> >> the ring pages that libxenguest allocates" ?
> >
> > Fine with me.
> >
> > Should I send another round, or can this be changed when committing?
> 
> Fixed on commit.  No need to resend just for this.
> 
> Question is whether Anthony has any view, or whether my R-by is good enough?

Patch looks good, so:
Acked-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>

Thanks,

-- 
Anthony PERARD