diff --git a/tests/Makefile.include b/tests/Makefile.include
index d39d5dd6a4..6618bfed70 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -97,7 +97,7 @@ endif
 # Controls the output generated by Avocado when running tests.
 # Any number of command separated loggers are accepted.  For more
 # information please refer to "avocado --help".
-AVOCADO_SHOW=app
+AVOCADO_SHOW?=app
 ifndef AVOCADO_TAGS
 	AVOCADO_CMDLINE_TAGS=$(patsubst %-softmmu,-t arch:%, \
 						 $(filter %-softmmu,$(TARGETS)))