From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Date: Tue, 29 May 2018 18:02:57 +0000
Subject: Re: [PATCH net] sctp: not allow to set rto_min with a value below 200 msecs
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To: Xin Long <lucien.xin@gmail.com>
Cc: Neal Cardwell <ncardwell@google.com>, Michael Tuexen <michael.tuexen@lurchi.franken.de>, Neil Horman <nhorman@tuxdriver.com>, Dmitry Vyukov <dvyukov@google.com>, Netdev <netdev@vger.kernel.org>, linux-sctp@vger.kernel.org, David Miller <davem@davemloft.net>, David Ahern <dsa@cumulusnetworks.com>, Eric Dumazet <edumazet@google.com>, syzkaller <syzkaller@googlegroups.com>

On Wed, May 30, 2018 at 01:45:08AM +0800, Xin Long wrote:
> If we're counting on max_t to fix this CPU stuck. It should not that
> matter if min rto < the value causing that stuck.

Yes but putting a floor to rto_{min,max} now is to protect the rtx
timer now, not the heartbeat one.

> 
> >
> > Anyway, what about we add a floor to rto_max too, so that RTO can
> > actually grow into something bigger that don't hog the CPU? Like:
> > rto_min floor = 5ms
> > rto_max floor = 50ms
> >
> >   Marcelo
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