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Date: Mon, 19 Aug 2024 18:01:31 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Yosry Ahmed <yosryahmed@google.com>
Cc: Nhat Pham <nphamcs@gmail.com>, Mike Yuan <me@yhndnzj.com>,
 linux-kernel@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.org,
 Muchun Song <muchun.song@linux.dev>, Shakeel Butt <shakeel.butt@linux.dev>,
 Roman Gushchin <roman.gushchin@linux.dev>, Michal Hocko
 <mhocko@kernel.org>, Johannes Weiner <hannes@cmpxchg.org>
Subject: Re: [PATCH] mm/memcontrol: respect zswap.writeback setting from
 parent cg too
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On Mon, 19 Aug 2024 12:05:44 -0700 Yosry Ahmed <yosryahmed@google.com> wrote:

> > Ah yeah, I was thinking this could be done in a follow-up patch.
> >
> > But yes, please - documentation. Preferably everything together as v2.
> >
> > >
> > > Also, do we want a Fixes tag and to backport this so that current
> > > users get the new behavior ASAP?
> >
> > Hmm, I wonder if it's more confusing for users to change the behavior
> > in older kernels.
> >
> > (OTOH, if this already is what people expect, then yeah it's a good
> > idea to backport).
> 
> My rationale is that if people will inevitably get the behavior change
> when they upgrade their kernel, I'd rather they get it sooner rather
> than later, before more users start depending on the old behavior.
> 
> I am guessing there is a chance this is not what backports are meant
> for. Andrew, any thoughts on this?

I agree.  It does depend on how long the old behavior has been out in
the field, and on our assessment of how many people are likely to
inconvenienced.  So... yes please, what is that Fixes:?