diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
index e50790e..1de3f94 100644
--- a/drivers/vfio/pci/vfio_pci_config.c
+++ b/drivers/vfio/pci/vfio_pci_config.c
@@ -727,7 +727,7 @@
 	p_setd(perm, 0, ALL_VIRT, NO_WRITE);
 
 	/* Writable bits mask */
-	mask =	PCI_ERR_UNC_TRAIN |		/* Training */
+	mask =	PCI_ERR_UNC_UND |		/* Undefined */
 		PCI_ERR_UNC_DLP |		/* Data Link Protocol */
 		PCI_ERR_UNC_SURPDN |		/* Surprise Down */
 		PCI_ERR_UNC_POISON_TLP |	/* Poisoned TLP */