pkt_sched: Fix gen_estimator locks

While passing a qdisc root lock to gen_new_estimator() and
gen_replace_estimator() dev could be deactivated or even before
grafting proper root qdisc as qdisc_sleeping (e.g. qdisc_create), so
using qdisc_root_lock() is not enough. This patch adds
qdisc_root_sleeping_lock() for this, plus additional checks, where
necessary.

Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c
index 8fa90d68ec6d..9b720adedead 100644
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -1839,7 +1839,7 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct nlattr **t
 
                 if (tca[TCA_RATE])
                         gen_replace_estimator(&cl->bstats, &cl->rate_est,
-                                              qdisc_root_lock(sch),
+                                              qdisc_root_sleeping_lock(sch),
                                               tca[TCA_RATE]);
                 return 0;
         }
@@ -1930,7 +1930,7 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct nlattr **t
 
         if (tca[TCA_RATE])
                 gen_new_estimator(&cl->bstats, &cl->rate_est,
-                                  qdisc_root_lock(sch), tca[TCA_RATE]);
+                                  qdisc_root_sleeping_lock(sch), tca[TCA_RATE]);
 
         *arg = (unsigned long)cl;
         return 0;