Re: [Xen-devel] [PATCH RFC 4/4] xen: arch-specific hooks for domain_soft_reset()

[Tim Deegan <tim@xxxxxxx>]

At 11:44 +0200 on 22 Jun (1434973458), Vitaly Kuznetsov wrote:
> Tim Deegan <tim@xxxxxxx> writes:
> 
> > At 15:35 +0200 on 03 Jun (1433345722), Vitaly Kuznetsov wrote:
> >> x86-specific hook cleans up the pirq-emuirq mappings and replaces the
> >> shared_info frame with an empty page to support subsequent
> >> XENMAPSPACE_shared_info call.
> >
> > That's a bit roundabout.  I think we might be better off allocating a
> > new shared-info page and abandoning the old one as an ordinary guest
> > RAM page.
> >
> 
> I've tried looking into such approach and there is an issue: shared_info
> page is being allocated from Xen heap and in case it's built with
> CONFIG_SEPARATE_XENHEAP we can't just reassign the page to the domain's
> pagelist or we'll open a possibility for a domain to move itself
> entirely to Xen's heap by e.g looping over all its gfns, doing
> XENMAPSPACE_shared_info and perforting soft reset.

Ah, true.  So your approach of replacing it is better.

Cheers,

Tim.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel