Keir Fraser wrote:
Need to bite the bullet and fix this properly by setting a software flag in ptes that are not subject to reference counting.
Could we get away with testing the VM_FOREIGN flag in vm_normal_page()? Although I get the impression that this wouldn't be easily justified if trying to merge with upstream Linux....
Unfortunately that also needs a hypervisor interface change, to allow setting of those pte flags. Easily done though, and we should definitely get that piece in for 3.2.0.
Alternatively, could we use the _PAGE_GNTTAB PTE flag that is used for debugging? Indeed, if we did this, could be obviate the need for the PTE-zapping hook, by instead catching the case where this flag is set, and unmapping the grant implicitly?
Otherwise, what would the semantics of this new flag be? Regards, Derek. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
