Re: 4.6.3 kernel panic on ppp interface termination (__tcf_hash_release / spinlock )

[Cong Wang <xiyou.wangcong@gmail.com>]

On Mon, Jul 4, 2016 at 12:07 PM,  <nuclearcat@nuclearcat.com> wrote:
> A little bit more details:
>
>  ~ # tc -s -d filter show dev ppp0 parent ffff:
> filter protocol ip pref 100 u32
> filter protocol ip pref 100 u32 fh 800: ht divisor 1
> filter protocol ip pref 100 u32 fh 800::1 order 1 key ht 800 bkt 0 flowid :1
> (rule hit 156 success 156)
>   match 00000000/00000000 at 12 (success 156 )
>         action order 1:  police 0x1 rate 4024Kbit burst 503000b mtu 2Kb
> action drop overhead 0b linklayer unspec
> ref 1 bind 1
>         Action statistics:
>         Sent 10564 bytes 156 pkt (dropped 0, overlimits 0 requeues 0)
>         backlog 0b 0p requeues 0
>
>
> Panic occurs when i delete ingress qdisc
>
> tc qdisc del dev ppp0 ingress
>
> After reversing commits (and some related commits)
>         1d4150c02c5709fdfd80f10368a31867de35e72e
>         ddf97ccdd7cb7e00daba465a5c947b8d941dc2a4
>
> Problem is not occurring.
>
> I'm not certainly sure this commits are causing issue, it is very hard to
> reverse patches on this particular system.
>

Can you check if the following commit helps?

commit a03e6fe569713fb3ff0714f8fd7c8785c0ca9e22
Author: WANG Cong <xiyou.wangcong@gmail.com>
Date:   Mon Jun 6 09:54:30 2016 -0700

    act_police: fix a crash during removal