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Subject: Re: [PATCH 00/10] OOM Debug print selection and additional
 information
To:     Michal Hocko <mhocko@kernel.org>, Edward Chron <echron@arista.com>
Cc:     Qian Cai <cai@lca.pw>, Andrew Morton <akpm@linux-foundation.org>,
        Roman Gushchin <guro@fb.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        David Rientjes <rientjes@google.com>,
        Shakeel Butt <shakeelb@google.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Ivan Delalande <colona@arista.com>
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From:   Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
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Date:   Wed, 28 Aug 2019 19:12:41 +0900
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On 2019/08/28 16:08, Michal Hocko wrote:
> On Tue 27-08-19 19:47:22, Edward Chron wrote:
>> For production systems installing and updating EBPF scripts may someday
>> be very common, but I wonder how data center managers feel about it now?
>> Developers are very excited about it and it is a very powerful tool but can I
>> get permission to add or replace an existing EBPF on production systems?
> 
> I am not sure I understand. There must be somebody trusted to take care
> of systems, right?
> 

Speak of my cases, those who take care of their systems are not developers.
And they afraid changing code that runs in kernel mode. They unlikely give
permission to install SystemTap/eBPF scripts. As a result, in many cases,
the root cause cannot be identified.

Moreover, we are talking about OOM situations, where we can't expect userspace
processes to work properly. We need to dump information we want, without
counting on userspace processes, before sending SIGKILL.