[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: [Xen-devel] TPR write optimization (even improves 2003 sp2)


  • To: "Keir Fraser" <keir.fraser@xxxxxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
  • From: "James Harper" <james.harper@xxxxxxxxxxxxxxxx>
  • Date: Thu, 8 Jan 2009 20:17:59 +1100
  • Cc:
  • Delivery-date: Thu, 08 Jan 2009 01:18:25 -0800
  • List-id: Xen developer discussion <xen-devel.lists.xensource.com>
  • Thread-index: AclwbQESFc81qMn2SR2vAjv2yU5MgQABpemAAAyUQdEAAFfuQAAAdgGuAAA1Q7AAAPb/BAAAN9OgAADpQpkAA5LWcAAAj3LQABWGf/AAA+R78AAR/80QAAAI8AAAADKq6gAAClig
  • Thread-topic: [Xen-devel] TPR write optimization (even improves 2003 sp2)

> On 08/01/2009 09:09, "James Harper" <james.harper@xxxxxxxxxxxxxxxx>
wrote:
> 
> >> Using alloc_xenheap_page would be okay.
> >
> > Is it possible to map a page allocated with alloc_domheap_page into
the
> > domain? The semantics must be different as it didn't work the way I
> > expected it to...
> 
> OTOH I think Intel's FlexPriority depends on us using
> alloc_domheap_pages(),
> so we may have an issue both ways round here.

I was afraid of that - I guess that's where the vmx side of things uses
the regs_page.

> The other issue with giving
> the guest write access to the APIC page is whether Xen can deal with
> random
> crap being written over it. Might need to audit vlapic.c for that.

Are you concerned about an errant (or malicious) DomU crashing the
vlapic code (and therefore Xen)? That was something I hadn't thought
of...

James

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.