| Message ID | 1459948214-735-1-git-send-email-larper@axis.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
On Wed, Apr 6, 2016 at 6:10 AM, Lars Persson <lars.persson@axis.com> wrote: > A failure in validate_xmit_skb_list() triggered an unconditional call > to dev_requeue_skb with skb=NULL. This slowly grows the queue > discipline's qlen count until all traffic through the queue stops. > Sounds reasonable. > Fixes: 55a93b3ea780 ("qdisc: validate skb without holding lock") > Signed-off-by: Lars Persson <larper@axis.com> > --- > net/sched/sch_generic.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c > index f18c350..1031536 100644 > --- a/net/sched/sch_generic.c > +++ b/net/sched/sch_generic.c > @@ -165,6 +165,9 @@ int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, > skb = dev_hard_start_xmit(skb, dev, txq, &ret); > > HARD_TX_UNLOCK(dev, txq); > + } else { > + spin_lock(root_lock); > + return qdisc_qlen(q); I think we should return 0 for this failure case so that qdisc_restart() will stop. How about teaching dev_requeue_skb() to skip skb==NULL case?
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index f18c350..1031536 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -165,6 +165,9 @@ int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, skb = dev_hard_start_xmit(skb, dev, txq, &ret); HARD_TX_UNLOCK(dev, txq); + } else { + spin_lock(root_lock); + return qdisc_qlen(q); } spin_lock(root_lock);
A failure in validate_xmit_skb_list() triggered an unconditional call to dev_requeue_skb with skb=NULL. This slowly grows the queue discipline's qlen count until all traffic through the queue stops. Fixes: 55a93b3ea780 ("qdisc: validate skb without holding lock") Signed-off-by: Lars Persson <larper@axis.com> --- net/sched/sch_generic.c | 3 +++ 1 file changed, 3 insertions(+)