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Date:   Mon, 4 Jun 2018 15:01:19 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Tejun Heo <tj@kernel.org>
Cc:     "Eric W. Biederman" <ebiederm@xmission.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Johannes Weiner <hannes@cmpxchg.org>, peterz@infradead.org,
        viro@zeniv.linux.org.uk, mingo@kernel.org,
        paulmck@linux.vnet.ibm.com, keescook@chromium.org, riel@redhat.com,
        tglx@linutronix.de, kirill.shutemov@linux.intel.com,
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        Balbir Singh <balbir@linux.vnet.ibm.com>,
        Oleg Nesterov <oleg@redhat.com>
Subject: Re: [RFC][PATCH 1/2] memcg: Ensure every task that uses an mm is in
 the same memory cgroup
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[dropping Kirill Tkhai from the CC because I get rejection from the mail
 server]

On Fri 01-06-18 12:16:52, Tejun Heo wrote:
> Hello,
> 
> On Fri, Jun 01, 2018 at 01:11:59PM -0500, Eric W. Biederman wrote:
> > Widening the definition of a process sounds good.  The memory control
> > group code would still need a way to forbid these in cgroup v1 mode,
> > when someone uses the task file.
> 
> Yeap, you're right.  We'll need memcg's can_attach rejecting for v1.

Do we really need? I mean, do we know about any existing usecase that
would need this weird threading concept and depend on memory migration
which doesn't really work?
-- 
Michal Hocko
SUSE Labs