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Date:   Thu, 21 Sep 2023 19:34:22 -0400
From:   "Liam R. Howlett" <Liam.Howlett@Oracle.com>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Matthew Wilcox <willy@infradead.org>,
        maple-tree@lists.infradead.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, pedro.falcato@gmail.com,
        stable <stable@kernel.org>
Subject: Re: [PATCH 0/2] maple_tree: Fix mas_prev() state regression.
Message-ID: <20230921233422.kv46hm4lddhp6rgb@revolver>
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* Andrew Morton <akpm@linux-foundation.org> [230921 19:27]:
> On Thu, 21 Sep 2023 20:23:11 +0100 Matthew Wilcox <willy@infradead.org> wrote:
> 
> > > > It isn't clear what are the user-visible effects of this flaw?  Please
> > > > send this along and I'll paste it in.
> > > 
> > > 
> > > User may notice that mas_prev() or mas_next() calls that result in going
> > > outside of the limit passed to the call will cause incorrect returns on
> > > subsequent calls using that maple state, such as mas_find() skipping an
> > > entry.
> > 
> > When Andrew says "User visible" he means "userspace visible".  Not
> > "in kernel user visible".  What are the _consequences_.
> 
> Thanks ;)
> 
> We have a Link:
> (https://gist.github.com/heatd/85d2971fae1501b55b6ea401fbbe485b) but it
> takes us to the reproducer code.  If it took us to Pedro's initial bug
> report then the sun would shine and birds would sing.
> 

I don't think the irc channel is logged so I'll respin with a cleaner
changelog for both patches and the subject of patch 1.

Thanks,
Liam