Re: [PATCH v2 2/2] qapi: Allow introspecting fix for savevm's cooperation with blockdev

[Markus Armbruster]

Peter Krempa <address@hidden> writes:

> savevm was buggy as it considered all monitor owned block device nodes

Recommend "monitor-owned block device nodes" or "block device nodes
owned by a monitor"

> for snapshot. With introduction of -blockdev the common usage made all
> nodes including protocol nodes monitor owned and thus considered for
> snapshot.

What exactly is / was the problem?

>           This was fixed but clients need to be able to detect whether
> this fix is present.

Fixed where?  Commit hash, if possible.

>
> Since savevm does not have an QMP alternative add the feature for the

Comma after alternative.

> 'human-monitor-command' backdoor which is used to call this command in
> modern use.

Eww.  I don't have better ideas short of "design and implement a sane
QMP interface to internal snapshots", which is too much work.

> Signed-off-by: Peter Krempa <address@hidden>
> ---
>  qapi/misc.json | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/qapi/misc.json b/qapi/misc.json
> index 6bd11f50e6..673445dfa9 100644
> --- a/qapi/misc.json
> +++ b/qapi/misc.json
> @@ -1020,6 +1020,12 @@
>  #
>  # @cpu-index: The CPU to use for commands that require an implicit CPU
>  #
> +# Features:
> +# @savevm-blockdev-monitor-nodes: If present, the savevm monitor command only

Maybe s/the savevm monitor command/HMP command savevm/

> +#                                 snapshots monitor owned nodes if they have 
> no

monitor-owned or owner by a monitor again.

> +#                                 parents. This allows to use 'savevm' with
> +#                                 -blockdev. (since 4.2)
> +#
>  # Returns: the output of the command as a string
>  #
>  # Since: 0.14.0
> @@ -1047,7 +1053,8 @@
>  ##
>  { 'command': 'human-monitor-command',
>    'data': {'command-line': 'str', '*cpu-index': 'int'},
> -  'returns': 'str' }
> +  'returns': 'str',
> +  'features' : [ { 'name': 'savevm-blockdev-monitor-nodes' } ] }

No space before ':'.

Short form would do:

     'features': [ 'savevm-blockdev-monitor-nodes' ]

>
>  ##
>  # @change: