On 11/2/20 10:25 PM, Yunsheng Lin wrote:
commit 2fb541c862c9 ("net: sch_generic: aviod concurrent reset and
enqueue op for lockless qdisc")
When the above upstream commit is backported to stable kernel, one assignment is missing, which causes two problems reported by Joakim and Vishwanath, see [1] and [2].
So add the assignment back to fix it.
https://urldefense.com/v3/__https://www.spinics.net/lists/netdev/msg693916.h...
https://urldefense.com/v3/__https://www.spinics.net/lists/netdev/msg695131.h...
Fixes: 749cc0b0c7f3 ("net: sch_generic: aviod concurrent reset and
enqueue op for lockless qdisc")
Signed-off-by: Yunsheng Lin linyunsheng@huawei.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 0e275e1..6e6147a 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -1127,10 +1127,13 @@ static void dev_deactivate_queue(struct
net_device *dev,
void *_qdisc_default) { struct Qdisc *qdisc = rtnl_dereference(dev_queue->qdisc); + struct Qdisc *qdisc_default = _qdisc_default;
if (qdisc) { if (!(qdisc->flags & TCQ_F_BUILTIN)) set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state);
+ rcu_assign_pointer(dev_queue->qdisc, qdisc_default); } }
I have tested the patch on v5.4.71 and it fixes our issues.
Tested-by: Vishwanath Pai vpai@akamai.com