Re: [PATCH v4 0/3] Adjust the output of x-query-virtio-status

[Markus Armbruster <armbru@redhat.com>]

"Michael S. Tsirkin" <mst@redhat.com> writes:

> On Wed, Feb 21, 2024 at 10:28:50PM +0800, Hyman Huang wrote:
>> v4:
>> - Rebase on master
>> - Fix the syntax mistake within the commit message of [PATCH v3 1/3]
>> - Adjust the linking file in hw/virtio/meson.build suggested by Markus
>> 
>> Please review,
>> Yong
>
> I'm still not excited about this.
> For one this will not scale when we add more than 64 feature bits.

x-query-virtio-status is meant to be a low effort, low level debugging
aid.  Its feature set members correspond 1:1 to uint64_t members of the
C struct, which I figure correspond 1:1 to 64-bit words in the binary
virtio interface.

If we run out of bits in the binary virtio interface, I guess we'd add
another 64-bit word.  The C struct acquires another uint64_t member, and
so does x-query-virtio-status.

What's wrong with that?

> As long as we are changing this let's address this please.
> I would also suggest just keeping the name in there, so
> a decoded feature will be
> [0, NAME]
> and a non-decoded will be just
> [23]
>
> will make for a smaller change.

I'm not sure I understand your suggestion.

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