Re: [Qemu-devel] QMP: RFC: I/O error info & query-stop-reason

[Anthony Liguori <anthony@codemonkey.ws>]

On 06/02/2011 04:06 AM, Daniel P. Berrange wrote:
> On Wed, Jun 01, 2011 at 04:35:03PM -0500, Anthony Liguori wrote:
>>>     "timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
>>>
>>> Valid error reasons could be: "enospc", "eio", etc.
>>
>> No etc :-)  Error reasons should we be well known and well documented.
>>
>>> B. query-stop-reason
>>> --------------------
>>>
>>> I also have a simple solution for item 2. The vm_stop() accepts a reason
>>> argument, so we could store it somewhere and return it as a string, like:
>>>
>>> ->   { "execute": "query-stop-reason" }
>>> <- { "return": { "reason": "user" } }
>>>
>>> Valid reasons could be: "user", "debug", "shutdown", "diskfull" (hey,
>>> this should be "ioerror", no?), "watchdog", "panic", "savevm", "loadvm",
>>> "migrate".
>>>
>>> Also note that we have a STOP event. It should be extended with the
>>> stop reason too, for completeness.
>>
>>
>> Can we just extend query-block?
>
> Primarily we want 'query-stop-reason' to tell us what caused the VM
> CPUs to stop. If that reason was 'ioerror', then 'query-block' could
> be used to find out which particular block device(s) caused the IO
> error to occurr&  get the "reason" that was in the BLOCK_IO_ERROR
> event.

My concern is that we're over abstracting here.  We're not going to add 
additional stop reasons in the future.

Maybe just add an 'io-error': True to query-state.

Regards,

Anthony Liguori

>
> Regards,
> Daniel