From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] sch_tbf: handle too small burst
Date: Sat, 23 Nov 2013 14:49:33 -0800 (PST)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Sat, 23 Nov 2013 12:59:20 -0800

> From: Eric Dumazet <edumazet@google.com>
> 
> If a too small burst is inadvertently set on TBF, we might trigger
> a bug in tbf_segment(), as 'skb' instead of 'segs' was used in a
> qdisc_reshape_fail() call.
> 
> tc qdisc add dev eth0 root handle 1: tbf latency 50ms burst 1KB rate
> 50mbit
> 
> Fix the bug, and add a warning, as such configuration is not
> going to work anyway for non GSO packets.
> 
> (For some reason, one has to use a burst >= 1520 to get a working
> configuration, even with old kernels. This is a probable iproute2/tc
> bug)
> 
> Based on a report and initial patch from Yang Yingliang
> 
> Fixes: e43ac79a4bc6 ("sch_tbf: segment too big GSO packets")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: Yang Yingliang <yangyingliang@huawei.com>

Applied and queued up for -stable.