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Date:   Mon, 14 Mar 2022 16:17:47 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Miaohe Lin <linmiaohe@huawei.com>
Cc:     akpm@linux-foundation.org, hughd@google.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/mlock: remove unneeded start >= vma->vm_end check
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On Mon, Mar 14, 2022 at 11:32:23PM +0800, Miaohe Lin wrote:
> If find_vma returns a vma, it must satisfies that start < vma->vm_end.
> Since vma list is sorted in the ascending order, so we will never see
> start >= vma->vm_end here. Remove this unneeded check.

faulty logic; vm_start + len might wrap.