On Sun, Jul 08, 2007 at 10:03:16PM -0700, Roland Dreier wrote: > Is the memory given to a domU always physically contiguous? If not, > what happens when a domU kernel does alloc_pages(GFP_KERNEL, 6) to try > and allocate 256 KB or something like that. Let's assume that the > domU kernel has enough guest contiguous pages to satisfy the > allocation -- is there any guarantee that the pages are really > physically contiguous?
according to Xen-dev alloc_pages does *not* guarantee contiguous pages. They say that the pci_alloc_consistent should be used instead. The question is whether non-Xen kernel *usually* allocates contiguous pages and so far it has been working and whether it should be fixed in the mainline of the driver. I do some tests (and also try to figure out how to change alloc_pages to pci_alloc_consistent) to verify contiguous pages. Anyway, thanks a lot!! -- Lukáš Hejtmánek _______________________________________________ general mailing list [email protected] http://lists.openfabrics.org/cgi-bin/mailman/listinfo/general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
