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charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221205_093842_211697_09CBDEC7 X-CRM114-Status: GOOD ( 26.57 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Mon, Dec 05, 2022 at 06:05:49PM +0100, Lorenzo Bianconi wrote: > > On Mon, Dec 05, 2022 at 12:14:41PM +0100, Lorenzo Bianconi wrote: > > > Introduce __mtk_wed_detach() in order to avoid a possible deadlock in > > > mtk_wed_attach routine if mtk_wed_wo_init fails. > > > Check wo pointer is properly allocated before running mtk_wed_wo_rese= t() > > > and mtk_wed_wo_deinit() in __mtk_wed_detach routine. > > > Honor mtk_wed_mcu_send_msg return value in mtk_wed_wo_reset(). > > >=20 > > > Fixes: 4c5de09eb0d0 ("net: ethernet: mtk_wed: add configure wed wo su= pport") > > > Signed-off-by: Lorenzo Bianconi > > > --- > > > Changes since v1: > > > - move wo pointer checks in __mtk_wed_detach() > > > --- > > > drivers/net/ethernet/mediatek/mtk_wed.c | 30 ++++++++++++++-----= -- > > > drivers/net/ethernet/mediatek/mtk_wed_mcu.c | 3 +++ > > > 2 files changed, 23 insertions(+), 10 deletions(-) > > >=20 > > > diff --git a/drivers/net/ethernet/mediatek/mtk_wed.c b/drivers/net/et= hernet/mediatek/mtk_wed.c > > > index d041615b2bac..2ce9fbb1c66d 100644 > > > --- a/drivers/net/ethernet/mediatek/mtk_wed.c > > > +++ b/drivers/net/ethernet/mediatek/mtk_wed.c > > > @@ -174,9 +174,10 @@ mtk_wed_wo_reset(struct mtk_wed_device *dev) > > > mtk_wdma_tx_reset(dev); > > > mtk_wed_reset(dev, MTK_WED_RESET_WED); > > > =20 > > > - mtk_wed_mcu_send_msg(wo, MTK_WED_MODULE_ID_WO, > > > - MTK_WED_WO_CMD_CHANGE_STATE, &state, > > > - sizeof(state), false); > > > + if (mtk_wed_mcu_send_msg(wo, MTK_WED_MODULE_ID_WO, > > > + MTK_WED_WO_CMD_CHANGE_STATE, &state, > > > + sizeof(state), false)) > > > + return; > > > =20 > > > if (readx_poll_timeout(mtk_wed_wo_read_status, dev, val, > > > val =3D=3D MTK_WED_WOIF_DISABLE_DONE, > > > @@ -576,12 +577,10 @@ mtk_wed_deinit(struct mtk_wed_device *dev) > > > } > > > =20 > > > static void > > > -mtk_wed_detach(struct mtk_wed_device *dev) > > > +__mtk_wed_detach(struct mtk_wed_device *dev) > > > { > > > struct mtk_wed_hw *hw =3D dev->hw; > > > =20 > > > - mutex_lock(&hw_lock); > > > - > > > mtk_wed_deinit(dev); > > > =20 > > > mtk_wdma_rx_reset(dev); > > > @@ -590,9 +589,11 @@ mtk_wed_detach(struct mtk_wed_device *dev) > > > mtk_wed_free_tx_rings(dev); > > > =20 > > > if (mtk_wed_get_rx_capa(dev)) { > > > - mtk_wed_wo_reset(dev); > > > + if (hw->wed_wo) > > > + mtk_wed_wo_reset(dev); > > > mtk_wed_free_rx_rings(dev); > > > - mtk_wed_wo_deinit(hw); > > > + if (hw->wed_wo) > > > + mtk_wed_wo_deinit(hw); > > > } > > > =20 > > > if (dev->wlan.bus_type =3D=3D MTK_WED_BUS_PCIE) { > > > @@ -612,6 +613,13 @@ mtk_wed_detach(struct mtk_wed_device *dev) > > > module_put(THIS_MODULE); > > > =20 > > > hw->wed_dev =3D NULL; > > > +} > > > + > > > +static void > > > +mtk_wed_detach(struct mtk_wed_device *dev) > > > +{ > > > + mutex_lock(&hw_lock); > > > + __mtk_wed_detach(dev); > > > mutex_unlock(&hw_lock); > > > } > > > =20 > > > @@ -1490,8 +1498,10 @@ mtk_wed_attach(struct mtk_wed_device *dev) > > > ret =3D mtk_wed_wo_init(hw); > > > } > > > out: > > > - if (ret) > > > - mtk_wed_detach(dev); > > > + if (ret) { > > > + dev_err(dev->hw->dev, "failed to attach wed device\n"); > > > + __mtk_wed_detach(dev); > > > + } > > > unlock: > > > mutex_unlock(&hw_lock); > > > =20 > > > diff --git a/drivers/net/ethernet/mediatek/mtk_wed_mcu.c b/drivers/ne= t/ethernet/mediatek/mtk_wed_mcu.c > > > index f9539e6233c9..3dd02889d972 100644 > > > --- a/drivers/net/ethernet/mediatek/mtk_wed_mcu.c > > > +++ b/drivers/net/ethernet/mediatek/mtk_wed_mcu.c > > > @@ -207,6 +207,9 @@ int mtk_wed_mcu_msg_update(struct mtk_wed_device = *dev, int id, void *data, > > > if (dev->hw->version =3D=3D 1) > > > return 0; > > > =20 > > > + if (!wo) > > > + return -ENODEV; > > > + > >=20 > > Can you please help me to understand how and when this mtk_wed_mcu_msg_= update() > > function is called? > >=20 > > I see this line .msg_update =3D mtk_wed_mcu_msg_update, and > > relevant mtk_wed_device_update_msg() define, but nothing calls to this > > define. >=20 > mtk_wed_device_update_msg() is currently run by mt7915 driver in > mt7915_mcu_wed_enable_rx_stats() and in mt76_connac_mcu_sta_wed_update(). I see, I didn't fetch latest net-next. > At the moment we always run mtk_wed_mcu_msg_update with non-NULL wo point= er, > but I would prefer to add this safety check. If it is impossible, please add WARN_ON(!wo) instead of "if ...". It describes better what is expected here. Thanks >=20 > Regards, > Lorenzo >=20 > >=20 > >=20 > >=20 > > > return mtk_wed_mcu_send_msg(wo, MTK_WED_MODULE_ID_WO, id, data, len, > > > true); > > > } > > > --=20 > > > 2.38.1 > > >=20 > >=20