[Qemu-devel] [PATCH v2 0/5] Allow memory_region_register_iommu_notifier() to fail

[Eric Auger <eric.auger@redhat.com>]

This series allows the memory_region_register_iommu_notifier()
to fail. As of now, when a MAP notifier is attempted to be
registered along with SMMUv3, Intel iommu without caching mode
or AMD IOMMU, we exit in the IOMMU MR notify_flag_changed()
callback. In case of VFIO assigned device hotplug, this could be
handled more nicely directly within the VFIO code, simply rejecting
the hotplug without exiting. This is what the series achieves
by handling the memory_region_register_iommu_notifier() returned
value.

Best Regards

Eric

This series can be found at:
https://github.com/eauger/qemu/tree/v4.1.0_register_iommu_notifier_fail_v2

History:

v1 -> v2:
- Intel IOMMU now handles the problem differently with machine init done
  notifier and machine hotplug allowed hook.
- use assert(!ret)
- message rewording in SMMUv3

Follow-up of "VFIO/SMMUv3: Fail on VFIO/HW nested paging detection"
https://patchew.org/QEMU/20190829090141.21821-1-eric.auger@redhat.com/


Eric Auger (5):
  memory: allow memory_region_register_iommu_notifier() to fail
  vfio/common: Handle memory_region_register_iommu_notifier() failure
  exec: assert on memory_region_register_iommu_notifier() failure
  vhost: assert on memory_region_register_iommu_notifier() failure
  amd_iommu: Let amdvi_iommu_notify_flag_changed() fail

 exec.c                |  6 ++++--
 hw/arm/smmuv3.c       | 12 +++++++-----
 hw/i386/amd_iommu.c   |  9 +++++----
 hw/i386/intel_iommu.c |  7 ++++---
 hw/ppc/spapr_iommu.c  |  7 ++++---
 hw/vfio/common.c      |  8 ++++++--
 hw/virtio/vhost.c     |  5 +++--
 include/exec/memory.h | 18 +++++++++++++-----
 memory.c              | 28 ++++++++++++++++++----------
 9 files changed, 64 insertions(+), 36 deletions(-)

-- 
2.20.1