Re: [Qemu-devel] [PATCH v2] hmp, qmp: introduce "info memory" and "query-memory" commands

[Markus Armbruster <armbru@redhat.com>]

Vadim Galitsyn <vadim.galitsyn@profitbricks.com> writes:

> Hi Markus,
>
> Thank you for the input.
>
>> However, your query-memory looks like it could fail.
>
> With the latest version of a patch (
> http://lists.nongnu.org/archive/html/qemu-devel/2017-06/msg03475.html)
> "query-memory" can fail only in two cases:
>
> a) if in QOM there is an object of type of TYPE_PC_DIMM which has no
> property of type PC_DIMM_SIZE_PROP, or
> b) PC_DIMM_SIZE_PROP is not represented as an integer.
>
> As far as I understand both (a) and (b) can happen only in case if QOM
> somehow corrupted which is not a normal case
> (please correct me if I am wrong).

These feel like programming errors.  They are impossible to test without
screwing up the program.  Untestable error recovery is commonly wrong.
I recommend to assert instead.  Igor, what do you think?

> Please also note, this is not the last version of the patch since new
> functionality was suggested
> to be included (NUMA information).
>
> If patch will be accepted, I think we would need a test case for it since
> command output differs once memory
> was hot-added/removed per given NUMA node. When final functionality will be
> negotiated, I will come up
> with test scenario and test case itself.

Thanks!