> -----Original Message----- > From: Jan Beulich [mailto:[email protected]] > Sent: 04 December 2018 15:21 > To: Paul Durrant <[email protected]> > Cc: Andrew Cooper <[email protected]>; Roger Pau Monne > <[email protected]>; Wei Liu <[email protected]>; George Dunlap > <[email protected]>; xen-devel <[email protected]> > Subject: Re: [PATCH v2 4/4] x86/mm/p2m: stop checking for IOMMU shared > page tables in mmio_order() > > >>> On 03.12.18 at 18:40, <[email protected]> wrote: > > Now that the iommu_map() and iommu_unmap() operations take an order > > parameter and elide flushing there's no strong reason why modifying MMIO > > ranges in the p2m should be restricted to a 4k granularity simply > because > > the IOMMU is enabled but shared page tables are not in operation. > > I'm afraid the two improvements are not enough for this restriction > to be lifted: There's still no preemption in the processing of the > higher order values.
Why? 1G orders are already ruled out and testing shows that 2M orders cause no problems on EPYC systems. Paul > > Jan > _______________________________________________ Xen-devel mailing list [email protected] https://lists.xenproject.org/mailman/listinfo/xen-devel
