net: sch_generic: fix the missing new qdisc assignment bug

When commit 2fb541c862 ("net: sch_generic: aviod concurrent reset and
enqueue op for lockless qdisc") 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://www.spinics.net/lists/netdev/msg693916.html
2. https://www.spinics.net/lists/netdev/msg695131.html

Fixes: 749cc0b0c7f3 ("net: sch_generic: aviod concurrent reset and enqueue op for lockless qdisc")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Yunsheng Lin 2020-11-03 11:25:38 +08:00 committed by Greg Kroah-Hartman
parent c5cf5c7b58
commit ebc24aeb86
1 changed files with 3 additions and 0 deletions

View File

@ -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);
}
}