Re: [PATCH rdma-next v3 8/8] IB/cm: Protect cm_dev, cm_ports and mad_agent with kref and lock

[Mark Zhang]

On 5/26/2021 4:00 AM, Jason Gunthorpe wrote:
> On Tue, May 11, 2021 at 11:22:12AM +0300, Leon Romanovsky wrote:
> > @@ -2139,6 +2197,8 @@ static int cm_req_handler(struct cm_work *work)
> >   		sa_path_set_dmac(&work->path[0],
> >   				 cm_id_priv->av.ah_attr.roce.dmac);
> >   	work->path[0].hop_limit = grh->hop_limit;
> > +
> > +	cm_destroy_av(&cm_id_priv->av);
> >   	ret = cm_init_av_by_path(&work->path[0], gid_attr, &cm_id_priv->av);
> >   	if (ret) {
> >   		int err;
>
> Why add cm_destroy_av() here? The cm_id_priv was freshly created at
> the top of this function and hasn't left the stack frame yet?
Because it was initialized by cm_init_av_for_response() previously, so 
destroy it here as cm_init_av_by_path() will re-initialize it.