diff --git a/arch/x86_64/kernel/pci-nommu.c b/arch/x86_64/kernel/pci-nommu.c
index c4c3cc3..aad7609 100644
--- a/arch/x86_64/kernel/pci-nommu.c
+++ b/arch/x86_64/kernel/pci-nommu.c
@@ -92,5 +92,7 @@
 {
 	if (dma_ops)
 		return;
+
+	force_iommu = 0; /* no HW IOMMU */
 	dma_ops = &nommu_dma_ops;
 }