Re: [PATCH net] fjes: Fix an error handling path in fjes_probe()

From: Michal Swiatkowski
Date: Wed Jan 04 2023 - 06:24:45 EST


On Thu, Dec 29, 2022 at 05:34:22PM +0100, Christophe JAILLET wrote:
> Le 21/12/2022 à 10:59, Michal Swiatkowski a écrit :
> > On Tue, Dec 20, 2022 at 09:57:06PM +0100, Christophe JAILLET wrote:
> > > A netif_napi_add() call is hidden in fjes_sw_init(). It should be undone
> > > by a corresponding netif_napi_del() call in the error handling path of the
> > > probe, as already done inthe remove function.
> > >
> > > Fixes: 265859309a76 ("fjes: NAPI polling function")
> > > Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> > > ---
> > > drivers/net/fjes/fjes_main.c | 4 +++-
> > > 1 file changed, 3 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/net/fjes/fjes_main.c b/drivers/net/fjes/fjes_main.c
> > > index 2513be6d4e11..01b4c9c6adbd 100644
> > > --- a/drivers/net/fjes/fjes_main.c
> > > +++ b/drivers/net/fjes/fjes_main.c
> > > @@ -1370,7 +1370,7 @@ static int fjes_probe(struct platform_device *plat_dev)
> > > adapter->txrx_wq = alloc_workqueue(DRV_NAME "/txrx", WQ_MEM_RECLAIM, 0);
> > > if (unlikely(!adapter->txrx_wq)) {
> > > err = -ENOMEM;
> > > - goto err_free_netdev;
> > > + goto err_del_napi;
> > > }
> > > adapter->control_wq = alloc_workqueue(DRV_NAME "/control",
> > > @@ -1431,6 +1431,8 @@ static int fjes_probe(struct platform_device *plat_dev)
> > > destroy_workqueue(adapter->control_wq);
> > > err_free_txrx_wq:
> > > destroy_workqueue(adapter->txrx_wq);
> > > +err_del_napi:
> > > + netif_napi_del(&adapter->napi);
> > > err_free_netdev:
> > > free_netdev(netdev);
> > > err_out:
> >
> > Reviewed-by: Michal Swiatkowski <michal.swiatkowski@xxxxxxxxxxxxxxx>
> >
> > I wonder if it won't be better to have fjes_sw_deinit() instead or
> > change fjes_sw_init to only netif_napi_add(). You know, to avoid another
> > bug here when someone add sth to the fjes_sw_deinit(). This is only
> > suggestion, patch looks fine.
>
> hi,
>
> based on Jakub's comment [1], free_netdev() already cleans up NAPIs (see
> [2]).
>
> So would it make more sense to remove netif_napi_del() from the .remove()
> function instead?
> The call looks useless to me now.
>
> CJ
>
> [1]: https://lore.kernel.org/all/20221221174043.1191996a@xxxxxxxxxx/
> [2]: https://elixir.bootlin.com/linux/v6.2-rc1/source/net/core/dev.c#L10710
>

Yeah, it make more sense.

Thanks, Michal
> >
> > > --
> > > 2.34.1
> > >
> >
>