intel-iommu: fail DEVIOTLB_UNMAP without dt mode

Without dt mode, device IOTLB notifier won't work since guest won't
send device IOTLB invalidation descriptor in this case. Let's fail
early instead of misbehaving silently.

Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Tested-by: Viktor Prutyanov <viktor@daynix.com>
Buglink: https://bugzilla.redhat.com/2156876
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230223065924.42503-3-jasowang@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index b520542c47199a63814d73267001f5553d2fb0c9..a6b35b07d241e960d9925c2632c847afaa8e136d 100644 (file)
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -3179,6 +3179,7 @@ static int vtd_iommu_notify_flag_changed(IOMMUMemoryRegion *iommu,
 {
     VTDAddressSpace *vtd_as = container_of(iommu, VTDAddressSpace, iommu);
     IntelIOMMUState *s = vtd_as->iommu_state;
+    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(s);
 
     /* TODO: add support for VFIO and vhost users */
     if (s->snoop_control) {
@@ -3193,6 +3194,13 @@ static int vtd_iommu_notify_flag_changed(IOMMUMemoryRegion *iommu,
                          PCI_FUNC(vtd_as->devfn));
         return -ENOTSUP;
     }
+    if (!x86_iommu->dt_supported && (new & IOMMU_NOTIFIER_DEVIOTLB_UNMAP)) {
+        error_setg_errno(errp, ENOTSUP,
+                         "device %02x.%02x.%x requires device IOTLB mode",
+                         pci_bus_num(vtd_as->bus), PCI_SLOT(vtd_as->devfn),
+                         PCI_FUNC(vtd_as->devfn));
+        return -ENOTSUP;
+    }
 
     /* Update per-address-space notifier flags */
     vtd_as->notifier_flags = new;