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

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2011-06-03 15:51, Anthony Liguori wrote:
> On 06/03/2011 08:41 AM, Jan Kiszka wrote:
>> On 2011-06-03 15:26, Anthony Liguori wrote:
>>> I think what we're getting at is the need for an enumeration.  So let's
>>> introduce one.  Here's what I propose:
>>>
>>> SQMP
>>> query-status
>>> ------------
>>>
>>> Return a json-object with the following information:
>>>
>>> - "running": true if the VM is running, or false if it is paused
>>> (json-bool)
>>> - "singlestep": true if the VM is in single step mode,
>>>                  false otherwise (json-bool)
>>> - "status": one of the following values (json-string) (optional)
>>>        "prelaunch" - QEMU was started with -S and guest has not started
>>>        "running" - guest is actively running
>>>        "singlestep" - guest is running in single step mode
>>
>> "singlestep" is just a subset of "debug" stops. Better use the latter.
>>
>>>        "paused" - guest has been paused via the 'stop' command
>>>        "postmigrate" - guest is paused following a successful 'migrate'
>>>        "shutdown" - guest is shut down (and -no-shutdown is in use)
>>>        "io-error" - the last IOP has failed and the device is configured
>>> to pause on I/O errors
>>>        "watchdog-error" - the watchdog action is configured to pause and
>>> has been triggered
>>
>> And "panic" or "internal-error".
> 
> Can you add the request help spec text too?  Is "internal-error" a KVM 
> emulation error?  If so, I'd rather make it "kvm-emulation-error".

It would currently map on VMSTOP_PANIC, which is KVM_EXIT_UNKNOWN,
KVM_EXIT_INTERNAL_ERROR or something arch-specific. Moreover, people may
put TCG errors or whatever under this stop reason in the future. If we
wanted "kvm-emulation-error", we would have to introduce
VMSTOP_KVM_EMULATION_ERROR.

But I think internal error is sufficiently precise for this purpose:
"Fatal internal error that prevents further guest execution."

Jan

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