Re: [Xen-devel] [PATCH RFC v2 1/4] x86/mm: Shadow and p2m changes for PV mem_access

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 22.08.14 at 22:13, <aravindp@xxxxxxxxx> wrote:
>>> Sigh, if only I could bound the CR0.WP solution :-(
>>
>>I wonder whether, in the case that mem_access is enabled, it would be
>>reasonable to perform the CR0.WP sections with interrupts disabled?
>>
>>The user/admin is already taking a performance hit from mem_access in the
>>first place, and delaying hardware interrupts a little almost certainly a 
>>lesser
>>evil than whatever mad scheme we devise to fix these issues.
>>
>>With interrupts disabled, the CR0.WP problem is very well bounded.  The only
>>faults which will occur will be as a direct result of the actions performed,
>>where the fault handlers will follow the extable redirection and return 
>>quickly.
> 
> I fine with using your approach and taking the performance hit especially 
> given that it is a corner case for mem_access listeners watching for Xen 
> writes to guest memory.
> 
> Jan, are you OK with it?

See the other reply to Andrew's mail I just sent.

Jan


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