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From:   Suren Baghdasaryan <surenb@google.com>
Date:   Thu, 19 Jan 2023 10:53:48 -0800
Message-ID: <CAJuCfpHXvm7XxivP-E1tm5M=E9y9F1W=avDAiDBSTLBNmTcn4A@mail.gmail.com>
Subject: Re: [PATCH 17/41] mm/mmap: move VMA locking before
 anon_vma_lock_write call
To:     Michal Hocko <mhocko@suse.com>
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On Thu, Jan 19, 2023 at 1:31 AM Michal Hocko <mhocko@suse.com> wrote:
>
> On Wed 18-01-23 13:48:13, Suren Baghdasaryan wrote:
> > On Wed, Jan 18, 2023 at 1:33 PM Michal Hocko <mhocko@suse.com> wrote:
> [...]
> > > So it will become:
> > > Move VMA flag modification (which now implies VMA locking) before
> > > vma_adjust_trans_huge() to ensure the modifications are done after VMA
> > > has been locked. Because vma_adjust_trans_huge() modifies the VMA and such
> > > modifications should be done under VMA write-lock protection.
> > >
> > > which is effectivelly saying
> > > vma_adjust_trans_huge() modifies the VMA and such modifications should
> > > be done under VMA write-lock protection so move VMA flag modifications
> > > before so all of them are covered by the same write protection.
> > >
> > > right?
> >
> > Yes, and the wording in the latter version is simpler to understand
> > IMO, so I would like to adopt it. Do you agree?
>
> of course.

Will update in the next respin. Thanks!

> --
> Michal Hocko
> SUSE Labs