RE: [PATCH 2/3] net/nfp: fix free resource problem

[Chaoyong He <chaoyong.he@corigine.com>]

> On 12/14/2023 10:24 AM, Chaoyong He wrote:
> > From: Long Wu <long.wu@corigine.com>
> >
> > Set the representor array to NULL to avoid that close interface does
> > not free some resource.
> >
> > Fixes: a135bc1644d6 ("net/nfp: fix resource leak for flower firmware")
> > Cc: chaoyong.he@corigine.com
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Long Wu <long.wu@corigine.com>
> > Reviewed-by: Chaoyong He <chaoyong.he@corigine.com>
> > Reviewed-by: Peng Zhang <peng.zhang@corigine.com>
> > ---
> >  drivers/net/nfp/flower/nfp_flower_representor.c | 15 ++++++++++++++-
> >  1 file changed, 14 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/nfp/flower/nfp_flower_representor.c
> > b/drivers/net/nfp/flower/nfp_flower_representor.c
> > index 27ea3891bd..5f7c1fa737 100644
> > --- a/drivers/net/nfp/flower/nfp_flower_representor.c
> > +++ b/drivers/net/nfp/flower/nfp_flower_representor.c
> > @@ -294,17 +294,30 @@ nfp_flower_repr_tx_burst(void *tx_queue,  static
> > int  nfp_flower_repr_uninit(struct rte_eth_dev *eth_dev)  {
> > +	uint16_t index;
> >  	struct nfp_flower_representor *repr;
> >
> >  	repr = eth_dev->data->dev_private;
> >  	rte_ring_free(repr->ring);
> >
> > +	if (repr->repr_type == NFP_REPR_TYPE_PHYS_PORT) {
> > +		index = NFP_FLOWER_CMSG_PORT_PHYS_PORT_NUM(repr-
> >port_id);
> > +		repr->app_fw_flower->phy_reprs[index] = NULL;
> > +	} else {
> > +		index = repr->vf_id;
> > +		repr->app_fw_flower->vf_reprs[index] = NULL;
> > +	}
> > +
> >  	return 0;
> >  }
> >
> >  static int
> > -nfp_flower_pf_repr_uninit(__rte_unused struct rte_eth_dev *eth_dev)
> > +nfp_flower_pf_repr_uninit(struct rte_eth_dev *eth_dev)
> >  {
> > +	struct nfp_flower_representor *repr = eth_dev->data->dev_private;
> > +
> > +	repr->app_fw_flower->pf_repr = NULL;
> >
> 
> Here it is assigned to NULL but is it freed? If freed, why not set to NULL where
> it is freed?
> 
> Same for above phy_reprs & vf_reprs.

The whole invoke view:
rte_eth_dev_close()
    --> nfp_flower_repr_dev_close()
        --> nfp_flower_repr_free()
            --> nfp_flower_pf_repr_uninit()
            --> nfp_flower_repr_uninit()
           // In these two functions, we just assigned to NULL but not freed yet.
           // It is still refer by the `eth_dev->data->dev_private`.
    --> rte_eth_dev_release_port()
        --> rte_free(eth_dev->data->dev_private);
        // And here it is really freed (by the rte framework).