Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
---
 tests/vm/Makefile.include | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/vm/Makefile.include b/tests/vm/Makefile.include
index 47084d5717c6..a018288b061c 100644
--- a/tests/vm/Makefile.include
+++ b/tests/vm/Makefile.include
@@ -25,6 +25,8 @@ vm-test:
 	@echo "  vm-boot-ssh-<guest>             - Boot guest and login via ssh"
 	@echo
 	@echo "Special variables:"
+	@echo "    DEBUG=1                       - be verbose, also start interactive"
+	@echo "	                                   shell on build failures"
 	@echo "    BUILD_TARGET=foo		 - override the build target"
 	@echo "    TARGET_LIST=a,b,c    	 - Override target list in builds."
 	@echo '    EXTRA_CONFIGURE_OPTS="..."'
-- 
2.18.1