From mboxrd@z Thu Jan  1 00:00:00 1970
From: Calvin Owens <calvinowens@fb.com>
Subject: Re: [PATCH] net: Use SK_MEM_QUANTUM as minimum for tcp/udp rmem/wmem
Date: Thu, 13 Aug 2015 14:07:04 -0700
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Cc: Sorin Dumitru <sorin@returnze.ro>,
	Sorin Dumitru <sdumitru@ixiacom.com>,
	David Miller <davem@davemloft.net>, <kuznet@ms2.inr.ac.ru>,
	<jmorris@namei.org>, <yoshfuji@linux-ipv6.org>, <kaber@trash.net>,
	netdev <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<kernel-team@fb.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Wednesday 08/12 at 10:46 -0700, Eric Dumazet wrote:
> On Wed, 2015-08-12 at 20:00 +0300, Sorin Dumitru wrote:
> 
> > Would clamping the values to a min value, like setsockopt(SO_SNDBUF)
> > does, be an option?
> > I still find it odd that SO_SNDBUF limits you, while the /proc
> > interface doesn't. If you think it's
> > too much, I'm ok with reverting it since it affects scripts.
> > 
> > On those arches where PAGE_SIZE == 64K(or > 16K) it looks like we have
> > tcp_wmem[1]
> > smaller than tcp_wmem[0]. Shouldn't we do something about this?
> 
> As long as we do not crash if/when root user changes /proc/sys/net
> settings, we are good.

Using "1 1 1" for tcp_{r,w}mem seems not to explode, so this sounds good
to me. I'll send a new patch reverting the original.

Thanks,
Calvin

> I would not care if performance is bad if root does something really
> stupid. root user is supposed to not mess things just for fun.