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SubjectRe: [PATCH] mm/mlock: remove unneeded start >= vma->vm_end check
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On 2022/3/15 0:17, Matthew Wilcox wrote:
> 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.

Many thanks for comment. I agree with you about "vm_start + len" might wrap.
But what I mean here is that we will never see "start" >= vma->vm_end here
as find_vma guarantees this. And I leave the "start + len <= vma->vm_start"
check untouched. So my cleanup should be right. Or am I miss something?

Thanks.

>
> .
>

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