Should we change the behaviour of -P for lsblk in util-linux for Jammy?

[Paride Legovini]

Bryce Harrington wrote on 18/02/2022:
> On Thu, Feb 17, 2022 at 01:00:07PM +1300, Matthew Ruffell wrote:
>> Hi all,
>>
>> I'm looking for a bit of advice about landing a new feature in util-linux, as
>> things have gotten a little complicated, and with feature freeze looming, a
>> second opinion would be much appreciated.
>>
>> e.g. lsblk -P now outputs LOG_SEC instead of LOG-SEC.
>>
>> So, what I need advice on is the next steps. Should we:
>>
>> 1) Do nothing, accept 2.32.2 behaviour for -P in Jammy, which is a change from
>> Focal/Impish, and will abruptly change again with the release of 2.38 likely to
>> land in KK. MAAS and Curtin are already fixed, no issues there, users must
>> upgrade to latest stable MAAS and curtin on Jammy release. Older Curtin and MAAS
>> will break.
>>
>> 2) Backport the new 10+ commits into 2.27.2 in Jammy and hope we don't cause any
>> regressions with the significant amount of code being changed. We keep the same
>> behaviour that users expect from Focal/Impish, and users can now use
>> -y / --shell if they want. Older MAAS and Curtin continue to work.
>>
>> 3) Revert the single patch which caused all of this,
>> 58b510e580 libsmartcols: sanitize variable names on export output
>> which is a tidier and well tested solution, and drop the patch when util-linux
>> is rebased to 2.38 in KK. This keeps existing behaviour in Focal/Impish, and
>> enables older MAAS and Curtin to keep working.
>>
>> I'm leaning toward suggesting 3) at this stage, but this is mostly to keep
>> existing users happy on their older versions of MAAS.
> 
> I think your hunch for #3 does sound like the safer approach to me as
> well.  Unless there's a huge number of users asking for the new feature,
> those who do need it can either wait until it's generally available, or
> use a workaround with some awk filters or whatnot.

I'm also +1 on option (3). The issue I can see with (3) is with
downstream software parsing  `lsblk --version` to know how to deal with
the output of -P. However (2) is not a solution for this (we'd still
diverge from the upstream behavior for that version) and option (1) has
the issues you mentioned.

Paride