Re: [PATCH 12/12] mm: change the contract for free_pgtables(), update docs

From: "Lorenzo Stoakes (ARM)" <ljs@kernel.org>
To: Suren Baghdasaryan <surenb@google.com>
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Subject: Re: [PATCH 12/12] mm: change the contract for free_pgtables(), update docs
Date: Tue, 8 Sep 2026 12:29:46 +0100	[thread overview]
Message-ID: <ap_xj3W3SjsnRBXv@gremlin> (raw)
In-Reply-To: <CAJuCfpH_v4YU+hsQDU_yQ4HZDf-2C6DuiJU5PGL+uVAsTwkZug@mail.gmail.com>

On Mon, Sep 07, 2026 at 09:53:43AM -0700, Suren Baghdasaryan wrote:
> On Tue, Sep 1, 2026 at 10:25 AM Lorenzo Stoakes (ARM) <ljs@kernel.org> wrote:
> > > > So, maybe something like:
> > > >
> > > >  * Note that free_pgtables(), used after unampping detached vmas, or when
> > > >  * exiting the whoel mm, does not take a page table lock before freeing a page
> > > >  * table.
> > > >  *
> > > >  * As page table freeing itself is RCU-safe, page table readers can safely run
> > > >  * concurrently with page table teardown. However, writers cannot, as without
> > > >  * a lock nothing prevents concurrent teardown.
> > > >  */
> > > >
> > > > Instead? What do you think?
> > >
> > > s/whoel/whole/
> >
> > Haha yup the inevitable typo...
>
> Also s/unampping/unmapping please.

Ack will fix on respin! I am the typo master ;)

--
Cheers, Lorenzo