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Date: Mon, 12 Feb 2024 17:53:12 -0500
From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
To: Lokesh Gidra <lokeshgidra@google.com>
Cc: akpm@linux-foundation.org, linux-fsdevel@vger.kernel.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH v4 3/3] userfaultfd: use per-vma locks in userfaultfd
 operations
Message-ID: <20240212225312.eq4aebhukeor5g3h@revolver>
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* Lokesh Gidra <lokeshgidra@google.com> [240212 17:31]:
> I have also introduced a handler for finding dst_vma and preparing its
> anon_vma, which is used in lock_vma() and find_vmas_mm_locked().
> 
> Sounds good?
> 
> > I've also thought of how you can name the abstraction in the functions:
> > use a 'prepare() and complete()' to find/lock and unlock what you need.
> > Might be worth exploring?  If we fail to 'prepare()' then we don't need
> > to 'complete()', which means there won't be mismatched locking hanging
> > around.  Maybe it's too late to change to this sort of thing, but I
> > thought I'd mention it.
> >
> Nice suggestion! But after (fortunately) finding the function names
> that are self-explanatory, dropping them seems like going in the wrong
> direction. Please let me know if you think this is a missing piece. I
> am open to incorporating this.

This plan sounds good, thanks!

Regards,
Liam