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Date:   Thu, 1 Nov 2018 11:30:50 +0100
From:   Michal Hocko <mhocko@kernel.org>
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        kirill.shutemov@linux.intel.com, aarcange@redhat.com,
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        yang.s@alibaba-inc.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Wind Yu <yuzhoujian@didichuxing.com>
Subject: Re: [PATCH v15 1/2] Reorganize the oom report in dump_header
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On Thu 01-11-18 18:09:39, 禹舟键 wrote:
> Hi Michal
> The null pointer is possible when calling the dump_header, this bug was
> detected by LKP. Below is the context 3 months ago.

Yeah I remember it was 0day report but I coundn't find it in my email
archive. Do you happen to have a message-id?

Anyway
        if (__ratelimit(&oom_rs))
                dump_header(oc, p);
+       if (oc)
+               dump_oom_summary(oc, victim);

Clearly cannot solve any NULL ptr because oc is never NULL unless I am
missing something terribly.
-- 
Michal Hocko
SUSE Labs