diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index f78e23f03938..57dc8fabc7d9 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -351,8 +351,12 @@ static struct amd_iommu *__rlookup_amd_iommu(u16 seg, u16 devid)
 	struct amd_iommu_pci_seg *pci_seg;
 
 	for_each_pci_segment(pci_seg) {
-		if (pci_seg->id == seg)
-			return pci_seg->rlookup_table[devid];
+		if (pci_seg->id != seg)
+			continue;
+		/* IVRS may not describe every device on the bus */
+		if (devid > pci_seg->last_bdf)
+			return NULL;
+		return pci_seg->rlookup_table[devid];
 	}
 	return NULL;
 }