diff options
| author | Konstantin Khlebnikov <khlebnikov@yandex-team.ru> | 2017-08-19 15:37:07 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-08-30 10:19:21 +0200 |
| commit | 58079f56b30227c37709e9db7e9b51204e81f4ea (patch) | |
| tree | 34617a03b7b5a66a3ffa843b2a1f2308b14d359f | |
| parent | 248af6aa226c5e3d503a26e109db944a1cabdb48 (diff) | |
net_sched: fix order of queue length updates in qdisc_replace()
[ Upstream commit 68a66d149a8c78ec6720f268597302883e48e9fa ]
This important to call qdisc_tree_reduce_backlog() after changing queue
length. Parent qdisc should deactivate class in ->qlen_notify() called from
qdisc_tree_reduce_backlog() but this happens only if qdisc->q.qlen in zero.
Missed class deactivations leads to crashes/warnings at picking packets
from empty qdisc and corrupting state at reactivating this class in future.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Fixes: 86a7996cc8a0 ("net_sched: introduce qdisc_replace() helper")
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | include/net/sch_generic.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index e5bba897d206..7a5d6a073165 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -717,8 +717,11 @@ static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new, old = *pold; *pold = new; if (old != NULL) { - qdisc_tree_reduce_backlog(old, old->q.qlen, old->qstats.backlog); + unsigned int qlen = old->q.qlen; + unsigned int backlog = old->qstats.backlog; + qdisc_reset(old); + qdisc_tree_reduce_backlog(old, qlen, backlog); } sch_tree_unlock(sch); |