On Wed, Mar 2, 2016 at 3:35 PM, Joerg Roedel <[email protected]> wrote: > On Wed, Mar 02, 2016 at 11:40:04AM +0300, David Kiarie wrote: >> What effect is setting the value next_bit to last invalidated index >> supposed to have ? > > The idea is to safe the IOTLB flush by not re-using the address-range > until the allocator wraps around to 0 again. We only allocate address > ranges between next_bit and end-of-range. This way we don't need a flush > after every unmap operation.
Okay, I'll look at this issue again. Last unrelated question. If I have 'iommu=pt' IOMMU doesn't seem to allocate any addresses and doesn't populate the 'root page table' until I try to pass-through a device. Why is that set like this ? > > > > Joerg > _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
