2022-09-05 19:18:59

by Cong Wang

[permalink] [raw]
Subject: Re: [PATCH net,v2] net: sched: tbf: don't call qdisc_put() while holding tree lock

On Fri, Aug 26, 2022 at 09:39:30AM +0800, Zhengchao Shao wrote:
> The issue is the same to commit c2999f7fb05b ("net: sched: multiq: don't
> call qdisc_put() while holding tree lock"). Qdiscs call qdisc_put() while
> holding sch tree spinlock, which results sleeping-while-atomic BUG.
>

Hm, did you see an actual warning here??

The commit you mentioned above is a classful Qdisc which accepts
user-specified child Qdisc, but TBF technically does not, I don't think
you can change its default fifo.

Thanks.