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

RE: [Xen-devel] [PATCH][UPDATE]Provide fast write emulation path



>From: Tim Deegan [mailto:Tim.Deegan@xxxxxxxxxx] 
>Sent: 2008年2月15日 19:36
>
>At 10:01 +0000 on 15 Feb (1203069706), Keir Fraser wrote:
>> I'd like a final ack from Tim on this one before applying.
>
>Ack.  
>
>I read through again and the only thing I can see is a risk that on SMP
>guests, a foreign vcpu might change the guest pagetable under our feet,
>leading to a risk of using inconsistent mappings for reads and writes.
>I think that's OK, though, because
> - we already have similar exposure from vTLB &c, and will do from OOS;
> - a guest with good TLB flush discipline should be entirely safe.
>

Yep. This is actually same as physical cpu behavior, as long as
inconsistent mappings are not stamped into shadow page table.

Thanks for comments,
Kevin

_______________________________________________
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®.