Re: [Qemu-devel] [PATCH v2 1/1] qmp.c: system_wakeup: adding RUN_STATE_SUSPENDED check before proceeding

[Eric Blake]

On 05/14/2018 04:50 PM, Daniel Henrique Barboza wrote:
> The qmp/hmp command 'system_wakeup' is simply a direct call to
> 'qemu_system_wakeup_request' from vl.c. This function verifies if
> runstate is SUSPENDED and if the wake up reason is valid before
> proceeding.
>
> However, no error or warning is thrown if any of those
> pre-requirements isn't met. There is no way for the caller to
> differentiate between a successful wakeup or an error state caused
> when trying to wake up a guest that wasn't suspended.

This would be the ideal place to also mention...

> This patch changes qmp_system_wakeup to make the runstate verification
> before proceeding to call qemu_system_wakeup_request, firing up
> an error message if the user tries to wake up a machine that
> isn't in SUSPENDED state. The change isn't made inside
> qemu_system_wakeup_request because it is used in migration,
> ACPI and others where this usage might be valid.
>
> Signed-off-by: Daniel Henrique Barboza <address@hidden>
> CC: Markus Armbruster <address@hidden>
> CC: Dr. David Alan Gilbert <address@hidden>
> CC: Eric Blake <address@hidden>
> ---
>
> This is a v2 of a patch that got buried:
>
> http://lists.gnu.org/archive/html/qemu-devel/2018-01/msg00092.html
>
> The changes in this version was all in the wording of the commit,
> reflecting the understanding reached in that discusssion:

...this text:

> silent
> failure should be interpreted as a bug and there is no API break
> in fixing this behavior - applications that didn't check the result
> will remain broken, the ones that check will have a chance to deal
> with it.

With the commit message further improved,
Reviewed-by: Eric Blake <address@hidden>

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Eric Blake, Principal Software Engineer
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