--- src/sys/bus/cam/scsi/scsi_da.c	2007/11/18 19:27:29	1.44
+++ src/sys/bus/cam/scsi/scsi_da.c	2007/11/21 21:28:41	1.45
@@ -1128,6 +1128,8 @@ daasync(void *callback_arg, u_int32_t co
 		cam_status status;
  
 		cgd = (struct ccb_getdev *)arg;
+		if (cgd == NULL)
+			break;
 
 		if (SID_TYPE(&cgd->inq_data) != T_DIRECT
 		    && SID_TYPE(&cgd->inq_data) != T_RBC