[PULL 04/10] vfio: Do not register any IOMMU_NOTIFIER_DEVIOTLB_UNMAP notifier

[Alex Williamson <alex.williamson@redhat.com>]

From: Eric Auger <eric.auger@redhat.com>

In an attempt to fix smmu/virtio-iommu - vhost regression, commit
958ec334bca3 ("vhost: Unbreak SMMU and virtio-iommu on dev-iotlb support")
broke virtio-iommu integration. This is due to the fact VFIO registers
IOMMU_NOTIFIER_ALL notifiers, which includes IOMMU_NOTIFIER_DEVIOTLB_UNMAP
and this latter now is rejected by the virtio-iommu. As a consequence,
the registration fails. VHOST behaves like a device with an ATC cache. The
VFIO device does not support this scheme yet.

Let's register only legacy MAP and UNMAP notifiers.

Fixes: 958ec334bca3 ("vhost: Unbreak SMMU and virtio-iommu on dev-iotlb support")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Message-Id: <20210209213233.40985-2-eric.auger@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---
 hw/vfio/common.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index d360d6f2da14..35a41fd05251 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -787,7 +787,7 @@ static void vfio_listener_region_add(MemoryListener *listener,
         iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
                                                        MEMTXATTRS_UNSPECIFIED);
         iommu_notifier_init(&giommu->n, vfio_iommu_map_notify,
-                            IOMMU_NOTIFIER_ALL,
+                            IOMMU_NOTIFIER_IOTLB_EVENTS,
                             section->offset_within_region,
                             int128_get64(llend),
                             iommu_idx);