diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index 0e2370663d..13c3c087fe 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -639,19 +639,13 @@ static int virtio_iommu_unmap(VirtIOIOMMU *s,
     return ret;
 }
 
-static ssize_t virtio_iommu_fill_resv_mem_prop(VirtIOIOMMU *s, uint32_t ep,
+static ssize_t virtio_iommu_fill_resv_mem_prop(IOMMUDevice *sdev, uint32_t ep,
                                                uint8_t *buf, size_t free)
 {
     struct virtio_iommu_probe_resv_mem prop = {};
     size_t size = sizeof(prop), length = size - sizeof(prop.head), total;
-    IOMMUDevice *sdev;
     GList *l;
 
-    sdev = container_of(virtio_iommu_mr(s, ep), IOMMUDevice, iommu_mr);
-    if (!sdev) {
-        return -EINVAL;
-    }
-
     total = size * g_list_length(sdev->resv_regions);
     if (total > free) {
         return -ENOSPC;
@@ -688,19 +682,27 @@ static int virtio_iommu_probe(VirtIOIOMMU *s,
                               uint8_t *buf)
 {
     uint32_t ep_id = le32_to_cpu(req->endpoint);
+    IOMMUMemoryRegion *iommu_mr = virtio_iommu_mr(s, ep_id);
     size_t free = VIOMMU_PROBE_SIZE;
+    IOMMUDevice *sdev;
     ssize_t count;
 
-    if (!virtio_iommu_mr(s, ep_id)) {
+    if (!iommu_mr) {
         return VIRTIO_IOMMU_S_NOENT;
     }
 
-    count = virtio_iommu_fill_resv_mem_prop(s, ep_id, buf, free);
+    sdev = container_of(iommu_mr, IOMMUDevice, iommu_mr);
+    if (!sdev) {
+        return -EINVAL;
+    }
+
+    count = virtio_iommu_fill_resv_mem_prop(sdev, ep_id, buf, free);
     if (count < 0) {
         return VIRTIO_IOMMU_S_INVAL;
     }
     buf += count;
     free -= count;
+    sdev->probe_done = true;
 
     return VIRTIO_IOMMU_S_OK;
 }
diff --git a/include/hw/virtio/virtio-iommu.h b/include/hw/virtio/virtio-iommu.h
index 70b8ace34d..1dd11ae81a 100644
--- a/include/hw/virtio/virtio-iommu.h
+++ b/include/hw/virtio/virtio-iommu.h
@@ -40,6 +40,7 @@ typedef struct IOMMUDevice {
     MemoryRegion root;          /* The root container of the device */
     MemoryRegion bypass_mr;     /* The alias of shared memory MR */
     GList *resv_regions;
+    bool probe_done;
 } IOMMUDevice;
 
 typedef struct IOMMUPciBus {