On Tue, Jun 10, 2008 at 10:24:06AM -0500, Anthony Liguori wrote: > If you add the MMIO page to the IOMMU table, then the behavior is > going to be identical to what occurs on bare metal which IMHO is a > good thing. Why jump through hoops to change what may or may not be > an error condition instead of letting the natural error behavior > happen? There may be some weird piece of hardware that relies on > this behavior out there.
One potential outcome of this behaviour on bare metal---which has been observed!---is a machine check. Letting the guest machine check the host is not a good thing. > There is no such thing as an MMIO slot. All you would need to do is > mmap(phys_ram_base + GPA, "/sys/bus/pci/.../region/0", MAP_SHARED | > MAP_FIXED) and you'd have a mixed slot assuming GPA was within an > existing RAM slot. That doesn't happen with the current code base, but color me convinced: we'll just continue checking gfns one by one when mapping them into the IOMMU page tables, skipping any non-ram gfns. Cheers, Muli -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
