Messages in this thread | | | Subject | Re: [PATCH stable] net: sch_generic: fix the missing new qdisc assignment bug | From | Vishwanath Pai <> | Date | Tue, 3 Nov 2020 10:46:28 -0500 |
| |
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. > > 1. https://urldefense.com/v3/__https://www.spinics.net/lists/netdev/msg693916.html__;!!GjvTz_vk!AqzcoNtwXeDu-vDNRKnOiOWYmi4B-2atZZExjZTvpp2jeJ9asOyQBVUtQyBp$ > 2. https://urldefense.com/v3/__https://www.spinics.net/lists/netdev/msg695131.html__;!!GjvTz_vk!AqzcoNtwXeDu-vDNRKnOiOWYmi4B-2atZZExjZTvpp2jeJ9asOyQBQlaitCQ$ > > 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>
| |