Re: [PATCH 4.19 13/99] netfilter: nf_conncount: fix argument order to find_next_bit

[Florian Westphal]

Andreas Hartmann <andihartmann@xxxxxxxxxxxxxxx> wrote:
> Since 4.19.17, I'm facing problems during streaming of videos I've never seen before. This means:
> 
> - video from internet stutters although enough data flow can be seen in bmon.
> - gpu is locked:
>   radeon 0000:0a:00.0: ring 0 stalled for more than 14084msec
>   radeon 0000:0a:00.0: GPU lockup (current fence id 0x0000000000053ed7 last fence id 0x0000000000053f0f on ring 0)
> - The connection of videos streamed locally by the machine for a TV suddenly breaks (upnp - serviio as server).
> 
> After very long time of testing, I detected, that removing the complete patch series for 4.19.17 regarding netfilter: nf_conncount makes the problem disappear.
> 
> Please remove / fix this patchset!

The state in 4.19.y is same as in mainline.
Could you at least tell us how you're using nf_conncount (nf/iptables
rules)?

Could you test with debugging (KASAN, CONFIG_PROVE_RCU etc). enabled?

I'm really surprised about this report, before the backport nf_conncount
caused frequent kernel crashes, how does reverting even work...?