diff --git a/drivers/s390/cio/cio_debug.h b/drivers/s390/cio/cio_debug.h index f88844adae1b..c9bf8989930f 100644 --- a/drivers/s390/cio/cio_debug.h +++ b/drivers/s390/cio/cio_debug.h @@ -23,6 +23,8 @@ extern debug_info_t *cio_debug_crw_id; static inline void CIO_HEX_EVENT(int level, void *data, int length) { + if (unlikely(!cio_debug_trace_id)) + return; while (length > 0) { debug_event(cio_debug_trace_id, level, data, length); length -= cio_debug_trace_id->buf_size;