diff --git a/sys/dev/asmc/asmc.c b/sys/dev/asmc/asmc.c
--- a/sys/dev/asmc/asmc.c
+++ b/sys/dev/asmc/asmc.c
@@ -791,23 +791,13 @@
 static int
 asmc_detach(device_t dev)
 {
-	struct asmc_softc *sc = device_get_softc(dev);
-
-	if (sc->sc_sms_tq) {
-		taskqueue_drain(sc->sc_sms_tq, &sc->sc_sms_task);
-		taskqueue_free(sc->sc_sms_tq);
-	}
-	if (sc->sc_cookie)
-		bus_teardown_intr(dev, sc->sc_irq, sc->sc_cookie);
-	if (sc->sc_irq)
-		bus_release_resource(dev, SYS_RES_IRQ, sc->sc_rid_irq,
-		    sc->sc_irq);
-	if (sc->sc_ioport)
-		bus_release_resource(dev, SYS_RES_IOPORT, sc->sc_rid_port,
-		    sc->sc_ioport);
-	mtx_destroy(&sc->sc_mtx);
 
-	return (0);
+	/*
+	 * Prevent module unload to avoid issues with device reprobing
+	 * via acpi_driver_added() which can cause kernel panics when
+	 * accessing freed driver structures.
+	 */
+	return (EBUSY);
 }
 
 static int