Date: Fri, 1 Jan 2016 10:33:53 +0900
From: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
To: "Serge E. Hallyn" <serge.hallyn@ubuntu.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Oleg Nesterov <oleg@redhat.com>, Peter Zijlstra <peterz@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Richard Guy Briggs <rgb@redhat.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        "Serge E. Hallyn" <serge@hallyn.com>, linux-kernel@vger.kernel.org
Subject: Re: [RFC] is_global_init() called on global init sub-thread
Message-ID: <20160101013353.GB532@swordfish>
References: <20151230062542.GA605@swordfish>
 <20160101010823.GB26243@mail.hallyn.com>
 <20160101011035.GA538@swordfish>
 <20160101011831.GA26628@mail.hallyn.com>
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On (12/31/15 19:18), Serge E. Hallyn wrote:
> On Fri, Jan 01, 2016 at 10:10:35AM +0900, Sergey Senozhatsky wrote:
> > On (12/31/15 19:08), Serge E. Hallyn wrote:
> > > > re-upping https://www.redhat.com/archives/linux-audit/2013-December/msg00086.html
> > > > 
> > > > Oleg Nesterov wrote:
> > > > 
> > > > :Because is_global_init() is only true for the main thread of /sbin/init.
> > > > :
> > > > :Just look at oom_unkillable_task(). It tries to not kill init. But, say,
> > > > :select_bad_process() can happily find a sub-thread of is_global_init()
> > > > :and still kill it.
> > > > 
> > > > this is still the case, isn't it? at least in some -stable kernels.
> > > > is there (or was there) any reason this change has never been committed?
> > > > (I'm particularly interested in is_global_init()).
> > > 
> > > ...  seems like it makes sense.  Can you remind us which init you're having
> > > to deal with?
> > > 
> > 
> > systemd
> > 
> > 	-ss
> 
> Well it makes sense to me.  The question is whether we are protecting the
> thing running as init, or the 'physical' thread with pid 1.  I think it's
> the former, so let's push on this.  Please resend the patch with a proper
> signed-off-by, and feel free to add

thanks. a bit puzzled, would reported-by Oleg and suggested-by Richard
be appropriate? (no objections if Oleg or Richard will submit it).

> Acked-by: Serge Hallyn <serge.hallyn@canonical.com>

	-ss
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