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Date: Mon, 29 May 2023 18:03:44 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Vlad Buslov <vladbu@nvidia.com>
Cc: Peilin Ye <yepeilin.cs@gmail.com>, Jamal Hadi Salim <jhs@mojatatu.com>,
 Pedro Tammela <pctammela@mojatatu.com>, "David S. Miller"
 <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>, Paolo Abeni
 <pabeni@redhat.com>, Cong Wang <xiyou.wangcong@gmail.com>, Jiri Pirko
 <jiri@resnulli.us>, Peilin Ye <peilin.ye@bytedance.com>, Daniel Borkmann
 <daniel@iogearbox.net>, "John Fastabend" <john.fastabend@gmail.com>, Hillf
 Danton <hdanton@sina.com>, <netdev@vger.kernel.org>, Cong Wang
 <cong.wang@bytedance.com>
Subject: Re: [PATCH v5 net 6/6] net/sched: qdisc_destroy() old ingress and
 clsact Qdiscs before grafting
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On Mon, 29 May 2023 15:58:50 +0300 Vlad Buslov wrote:
> If livelock with concurrent filters insertion is an issue, then it can
> be remedied by setting a new Qdisc->flags bit
> "DELETED-REJECT-NEW-FILTERS" and checking for it together with
> QDISC_CLASS_OPS_DOIT_UNLOCKED in order to force any concurrent filter
> insertion coming after the flag is set to synchronize on rtnl lock.

Sounds very nice, yes.