From: Cong Wang <[email protected]>
Date: Thu, 21 Dec 2017 16:03:29 -0800
> qdisc_reset() should always be called with qdisc spinlock
> and with BH disabled, otherwise qdisc ->reset() could race
> with TX BH.
>
> Fixes: 7bbde83b1860 ("net: sched: drop qdisc_reset from dev_graft_qdisc")
> Reported-by: Jakub Kicinski <[email protected]>
> Cc: John Fastabend <[email protected]>
> Signed-off-by: Cong Wang <[email protected]>
There doesn't seem to be agreement over whether qdisc_reset() really
needs to run with the lock held. In fact, the general consensus is
that this really shouldn't run until a grace period had occurred and
therefore parallel TX paths cannot be running any longer.
In any event, this was supposed to work towards a bug fix which
ultimately was fixed instead with the ptr_ring change from John.
So this seems unnecessary now.
If you disagree, please repost with an updated commit message which
explains things further.
Thank you.
