tests/qmp-test: Demonstrate QMP errors jumping the queue

When OOB is enabled, out-of-band commands are executed right away,
everything else is queued.  This lets out-of-band commands "jump the
queue".

However, certain errors are always reported right away, and therefore
can jump the queue even when the erroneous input does not request
out-of-band execution.  These errors are pretty unlikely to occur in
production, but it's wrong all the same.  Mark FIXME.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180703085358.13941-17-armbru@redhat.com>

diff --git a/monitor.c b/monitor.c
index 37ca4e798dc7fe69ea052dbd495a2fc1ce05b4ff..c49214cd8fc78e7bd65863eb38f13d05caf8d8d4 100644 (file)
--- a/monitor.c
+++ b/monitor.c
@@ -4339,6 +4339,7 @@ static void handle_qmp_command(JSONMessageParser *parser, GQueue *tokens)
     return;
 
 err:
+    /* FIXME overtakes queued in-band commands, wrong when !qmp_is_oob() */
     monitor_qmp_respond(mon, NULL, err, NULL);
     qobject_unref(req);
 }

diff --git a/tests/qmp-test.c b/tests/qmp-test.c
index a7b6ec98e4b1f9cb47173b1aacece926c7eff90e..9eb20a1a18bf82dfe5044872204c23ea0c274c80 100644 (file)
--- a/tests/qmp-test.c
+++ b/tests/qmp-test.c
@@ -241,6 +241,13 @@ static void test_qmp_oob(void)
     unblock_blocked_cmd();
     recv_cmd_id(qts, "ib-blocks-1");
     recv_cmd_id(qts, "ib-quick-1");
+
+    /* FIXME certain in-band errors overtake slow in-band command */
+    send_cmd_that_blocks(qts, "blocks-2");
+    qtest_async_qmp(qts, "{ 'id': 'err-2' }");
+    recv_cmd_id(qts, NULL);
+    unblock_blocked_cmd();
+    recv_cmd_id(qts, "blocks-2");
     cleanup_blocking_cmd();
 
     qtest_quit(qts);