Re: [Qemu-devel] [PATCH 16/32] tests/qmp-test: Demonstrate QMP errors jumping the queue

[Markus Armbruster]

Peter Xu <address@hidden> writes:

> On Mon, Jul 02, 2018 at 06:22:02PM +0200, Markus Armbruster wrote:
>> 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 <address@hidden>
>> ---
>>  monitor.c        | 1 +
>>  tests/qmp-test.c | 7 +++++++
>>  2 files changed, 8 insertions(+)
>> 
>> diff --git a/monitor.c b/monitor.c
>> index 51ba1485ad..28fa9b8d44 100644
>> --- a/monitor.c
>> +++ b/monitor.c
>> @@ -4338,6 +4338,7 @@ 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 dc30930201..fe5e5b548a 100644
>> --- a/tests/qmp-test.c
>> +++ b/tests/qmp-test.c
>> @@ -239,6 +239,13 @@ 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);
>
> (I thought the "id" will be passed in when reply with the error,
>  though in fact it's not)

It will be after the next patch :)

> Thanks for the test case.  I'll work upon it when fixing that up.
>
> Reviewed-by: Peter Xu <address@hidden>
>
>> +    unblock_blocked_cmd();
>> +    recv_cmd_id(qts, "blocks-2");
>>      cleanup_blocking_cmd();
>>  
>>      qtest_quit(qts);
>> -- 
>> 2.17.1
>>