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Date:   Mon, 31 Jan 2022 14:44:55 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Michel Lespinasse <michel@lespinasse.org>
Cc:     Linux-MM <linux-mm@kvack.org>, linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>, kernel-team@fb.com,
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        Suren Baghdasaryan <surenb@google.com>,
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        Axel Rasmussen <axelrasmussen@google.com>,
        Andy Lutomirski <luto@kernel.org>
Subject: Re: [PATCH v2 12/35] mm: separate mmap locked assertion from find_vma
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References: <20220128131006.67712-1-michel@lespinasse.org>
 <20220128131006.67712-13-michel@lespinasse.org>
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On Fri, Jan 28, 2022 at 05:09:43AM -0800, Michel Lespinasse wrote:
> This adds a new __find_vma() function, which implements find_vma minus
> the mmap_assert_locked() assertion.
> 
> find_vma() is then implemented as an inline wrapper around __find_vma().

You might like to take inspiration from the maple tree patches
where we assert that either the RCU lock is held or the mmap_lock
is held.