Re: [PATCH v2] docs: specify stability of hypfs path documentation

[George Dunlap <George.Dunlap@xxxxxxxxxx>]

> On Jul 13, 2020, at 3:47 PM, Jan Beulich <JBeulich@xxxxxxxx> wrote:
> 
> On 13.07.2020 16:03, Juergen Gross wrote:
>> In docs/misc/hypfs-paths.pandoc the supported paths in the hypervisor
>> file system are specified. Make it more clear that path availability
>> might change, e.g. due to scope widening or narrowing (e.g. being
>> limited to a specific architecture).
>> 
>> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
>> Release-acked-by: Paul Durrant <paul@xxxxxxx>
> 
> Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
> 
> However, I'd like agreement by at least one other REST maintainer on
> ...
> 
>> @@ -55,6 +58,11 @@ tags enclosed in square brackets.
>> * CONFIG_* -- Path is valid only in case the hypervisor was built with
>>   the respective config option.
>> 
>> +In case a tag for a path indicates that this path is available in some
>> +case only, this availability might be extended or reduced in future by
>> +modification or removal of the tag. A path once assigned meaning won't go
>> +away altogether or change its meaning, though.
> 
> ... the newly imposed guarantee we're now making. We really want to
> avoid declaring something as stable without being quite certain we
> can keep it stable.

The declaration of new nodes must all happen in this file, right?  So as long 
as the maintainer(s) fo this file are aware of that, and it’s commented so that 
people know that expecation, I think it’s OK.

But I think this paragraph isn’t very clear to me what “might be extended or 
reduced …but won’t go away altogether”.

IT sounds like you’re saying:

1. Paths listed without conditions will always be available

2. Paths listed with conditions may be extended: i.e., a node currently listed 
as PV might also become available for HVM guests

3. Paths listed with conditions might have those conditions reduced, but will 
never entirely disappear.  So something currently listed as PV might be reduced 
to CONFIG_HAS_FOO, but won’t be completely removed.

Is that what you meant?

 -George