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To:     Muchun Song <songmuchun@bytedance.com>,
        Xiongchun duan <duanxiongchun@bytedance.com>,
        linux-mm@kvack.org
Cc:     linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] mm/ksm: Fix a null pointer dereference
From:   Markus Elfring <Markus.Elfring@web.de>
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Date:   Tue, 14 Apr 2020 09:14:17 +0200
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> The find_mergeable_vma can return NULL. In this case, it leads
> to crash when we access vma->vm_mm(which's offset is 0x40) in

I suggest to improve the commit message.

* Wording alternative:
  to a crash when we access vma->vm_mm (its offset is 0x40) in

* Can a function name be nicer than the information =E2=80=9Cat 0000000000=
000040=E2=80=9D
  in the patch subject?

* Would you like to add the tag =E2=80=9CFixes=E2=80=9D to the change desc=
ription?

Regards,
Markus