>>> On 11.08.17 at 18:43, <roger....@citrix.com> wrote: > On certain Intel systems, as far as I can tell almost all pre-Haswell ones, > trying to boot a PVH Dom0 will freeze the box completely, up to the point that > not even the watchdog works. The freeze happens exactly when enabling the DMA > remapping in the IOMMU, the last line seen is: > > (XEN) [VT-D]iommu_enable_translation: iommu->reg = ffff82c00021b000 > > In order to workaround this (which seems to be a lack of proper RMRR entries, > plus the IOMMU being unable to generate faults and freezing the entire system) > add a PVH specific implementation of iommu_inclusive_mapping, that maps > non-RAM, non-unusable regions into Dom0 p2m. Note that care is taken to not > map > device MMIO regions that Xen is emulating, like the local APIC or the IO APIC. > > Signed-off-by: Roger Pau Monné <roger....@citrix.com>
I don't mean to object to the patch, but it certainly would be helpful to understand the behavior a little better, in particular also to perhaps be able to derive what RMRRs are missing (which could then be added via command line option instead of this all-or-norhing approach). Kevin, could you perhaps help here? Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
