Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Message-ID: <1524673273.8257.2.camel@gmx.de>
Subject: Re: DOS by unprivileged user
From:   Mike Galbraith <efault@gmx.de>
To:     Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc:     Ferry Toth <ftoth@telfort.nl>, linux-kernel@vger.kernel.org
Date:   Wed, 25 Apr 2018 18:21:13 +0200
In-Reply-To: <20180425155459.5a4e40e0@alans-desktop>
References: <9023506.UBh6vynRGa@delfion> <4285098.DEWjdbWF2X@delfion>
         <1524325275.8078.2.camel@gmx.de> <6057755.ozdVOybsI6@delfion>
         <1524470676.5451.1.camel@gmx.de> <20180425155459.5a4e40e0@alans-desktop>
Content-Type: text/plain; charset="ISO-8859-15"
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Wed, 2018-04-25 at 15:54 +0100, Alan Cox wrote:
> > > I think memory allocation and io waits can't be decoupled from
> > > scheduling as they are now.  
> > 
> > The scheduler is not decoupled from either, it is intimately involved
> > in both.  However, none of the decision making smarts for either reside
> > in the scheduler, nor should they.
> 
> It belongs in both.

If mm decision making belongs within the process scheduler, it follows
that IO requests, dirty page writeback etc. do as well.  Nope, I don't
think we want to create a squid-uler, with tentacles extending all over
the dang kernel.

The thrashing problem could use some attention, but we'll have to agree
to disagree about the scheduler growing mm, io (etc) smarts.

	-Mike