diff --git a/tests/qemu-iotests/099 b/tests/qemu-iotests/099
index ffc7ea795a..132aa0b228 100755
--- a/tests/qemu-iotests/099
+++ b/tests/qemu-iotests/099
@@ -107,8 +107,21 @@ echo
 # generate a JSON object here as well
 test_qemu "file.driver=blkverify,file.raw.filename=$TEST_IMG.compare,file.test.file.driver=blkdebug,file.test.file.image.filename=$TEST_IMG,file.test.file.inject-error.0.event=l1_update"
 
+echo
+echo '=== Testing plain filename for blkdebug ==='
+echo
 
-rm -f "$TEST_IMG.compare"
+touch "$TEST_DIR/blkdebug.conf"
+test_qemu "file.driver=blkdebug,file.config=$TEST_DIR/blkdebug.conf,file.image.filename=$TEST_IMG"
+
+echo
+echo '=== Testing plain filename for blkdebug without configuration file ==='
+echo
+
+test_qemu "file.driver=blkdebug,file.image.filename=$TEST_IMG"
+
+
+rm -f "$TEST_IMG.compare" "$TEST_DIR/blkdebug.conf"
 
 # success, all done
 echo "*** done"
diff --git a/tests/qemu-iotests/099.out b/tests/qemu-iotests/099.out
index 50cc527fb2..2fa06ff3a0 100644
--- a/tests/qemu-iotests/099.out
+++ b/tests/qemu-iotests/099.out
@@ -17,4 +17,12 @@ json:{"driver": "IMGFMT", "file": {"image": {"driver": "file", "filename": "TEST
 === Testing indirectly enforced JSON filename ===
 
 json:{"driver": "raw", "file": {"test": {"driver": "IMGFMT", "file": {"image": {"driver": "file", "filename": "TEST_DIR/t.IMGFMT"}, "driver": "blkdebug", "inject-error.0.event": "l1_update"}}, "driver": "blkverify", "raw": {"driver": "file", "filename": "TEST_DIR/t.IMGFMT.compare"}}}
+
+=== Testing plain filename for blkdebug ===
+
+blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/t.IMGFMT
+
+=== Testing plain filename for blkdebug without configuration file ===
+
+blkdebug::TEST_DIR/t.IMGFMT
 *** done