From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Subject: Re: [PATCH v2 0/2] net/sctp: Avoid allocating high order memory with
 kmalloc()
Date: Fri, 3 Aug 2018 17:30:09 -0300
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Cc: 'Konstantin Khorenko' <khorenko@virtuozzo.com>,
        "oleg.babin@gmail.com" <oleg.babin@gmail.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-sctp@vger.kernel.org" <linux-sctp@vger.kernel.org>,
        "David S . Miller" <davem@davemloft.net>,
        Vlad Yasevich <vyasevich@gmail.com>,
        Neil Horman <nhorman@tuxdriver.com>,
        Xin Long <lucien.xin@gmail.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Michael Tuexen <michael.tuexen@lurchi.franken.de>
To: David Laight <David.Laight@aculab.com>
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On Fri, Aug 03, 2018 at 04:43:28PM +0000, David Laight wrote:
> From: Konstantin Khorenko
> > Sent: 03 August 2018 17:21
> > 
> > Each SCTP association can have up to 65535 input and output streams.
> > For each stream type an array of sctp_stream_in or sctp_stream_out
> > structures is allocated using kmalloc_array() function. This function
> > allocates physically contiguous memory regions, so this can lead
> > to allocation of memory regions of very high order, i.e.:
> ...
> 
> Given how useless SCTP streams are, does anything actually use
> more than about 4?

Maybe Michael can help us with that. I'm also curious now.

  Marcelo