Re: INFO: task hung in tcf_ife_init

[Cong Wang]

On Thu, Sep 3, 2020 at 2:47 AM Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote:
> This commit might be related :
>
> commit 4e407ff5cd67ec76eeeea1deec227b7982dc7f66
> Author: Cong Wang <xiyou.wangcong@xxxxxxxxx>
> Date:   Sun Aug 19 12:22:12 2018 -0700
>
>     act_ife: move tcfa_lock down to where necessary

It does not look like my commit's fault. From my _quick_ understanding
of this problem, we somehow have a "deadlock" situation:

Thread A allocates an IDR with a specific index and calls populate_metalist()
to re-accquire the RTNL lock.

Thread B gets RTNL lock right after thread A releases it, then it waits for
thread A to finally commit the IDR change.

Thanks.