# Re: \[PATCH RFC 4/7\] bridge: cfm: Kernel space implementation of CFM.

- From: Jakub Kicinski \<kuba@kernel.org\>
- Date: 2020-09-04 15:03:04 
- List: netdev
- Page: https://ratatoskr.run/netdev/2020/09/6094368
- Thread: https://ratatoskr.run/netdev/2020/09/6093916/t.md

```text
On Fri, 4 Sep 2020 09:15:24 +0000 Henrik Bjoernlund wrote:
> +	rcu_read_lock();
> +	b_port = rcu_dereference(mep->b_port);
> +	if (!b_port)
> +		return NULL;
> +	skb = dev_alloc_skb(CFM_CCM_MAX_FRAME_LENGTH);
> +	if (!skb)
> +		return NULL;

net/bridge/br_cfm.c:171:23: warning: context imbalance in 'ccm_frame_build' - different lock contexts for basic block
```