diff --git a/sys/dev/fdc/fdc.c b/sys/dev/fdc/fdc.c
index 4fee4f527fa..04bffb044e8 100644
--- a/sys/dev/fdc/fdc.c
+++ b/sys/dev/fdc/fdc.c
@@ -846,7 +846,8 @@ fdc_attach(device_t dev)
 		return error;
 	}
 	error = BUS_SETUP_INTR(device_get_parent(dev), dev, fdc->res_irq,
-			       INTR_TYPE_BIO, fdc_intr, fdc, &fdc->fdc_intr);
+			       INTR_TYPE_BIO | INTR_ENTROPY, fdc_intr, fdc,
+			       &fdc->fdc_intr);
 	if (error) {
 		device_printf(dev, "cannot setup interrupt\n");
 		return error;
diff --git a/sys/isa/fd.c b/sys/isa/fd.c
index 4fee4f527fa..04bffb044e8 100644
--- a/sys/isa/fd.c
+++ b/sys/isa/fd.c
@@ -846,7 +846,8 @@ fdc_attach(device_t dev)
 		return error;
 	}
 	error = BUS_SETUP_INTR(device_get_parent(dev), dev, fdc->res_irq,
-			       INTR_TYPE_BIO, fdc_intr, fdc, &fdc->fdc_intr);
+			       INTR_TYPE_BIO | INTR_ENTROPY, fdc_intr, fdc,
+			       &fdc->fdc_intr);
 	if (error) {
 		device_printf(dev, "cannot setup interrupt\n");
 		return error;