[bug report] WARNING: possible circular locking at: rdma_destroy_id+0x17/0x20 [rdma_cm] triggered by blktests nvmeof-mp/002

[Bart Van Assche]

On 5/25/22 13:01, Sagi Grimberg wrote:
> iirc this was reported before, based on my analysis lockdep is giving
> a false alarm here. The reason is that the id_priv->handler_mutex cannot
> be the same for both cm_id that is handling the connect and the cm_id
> that is handling the rdma_destroy_id because rdma_destroy_id call
> is always called on a already disconnected cm_id, so this deadlock
> lockdep is complaining about cannot happen.
> 
> I'm not sure how to settle this.

If the above is correct, using lockdep_register_key() for 
id_priv->handler_mutex instead of a static key should make the lockdep 
false positive disappear.

Thanks,

Bart.