From: Cong Wang <xiyou.wangc...@gmail.com>
Date: Thu, 21 Dec 2017 16:03:30 -0800
> __skb_array_empty() is only safe if array is never resized.
> pfifo_fast_dequeue() is called in TX BH context and without
> qdisc lock, so even after we disable BH on ->reset() path
> we can still race with other CPU's.
>
> Fixes: c5ad119fb6c0 ("net: sched: pfifo_fast use skb_array")
> Reported-by: Jakub Kicinski <jakub.kicin...@netronome.com>
> Cc: John Fastabend <john.fastab...@gmail.com>
> Signed-off-by: Cong Wang <xiyou.wangc...@gmail.com>
Based upon the discussion over this patch, this bug is ultimately fixed
by John's patch which adds a dummy element at the end of allocated
ptr_ring queues.
And I've just applied that.
