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micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="FiFvvHc0xRrwB4HC" Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221204_070933_249252_41D9247A X-CRM114-Status: GOOD ( 20.90 ) 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 --FiFvvHc0xRrwB4HC Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > On Fri, Dec 02, 2022 at 06:36:33PM +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. > >=20 > > Fixes: 4c5de09eb0d0 ("net: ethernet: mtk_wed: add configure wed wo supp= ort") > > Signed-off-by: Lorenzo Bianconi > > --- > > drivers/net/ethernet/mediatek/mtk_wed.c | 24 ++++++++++++++------- > > drivers/net/ethernet/mediatek/mtk_wed_mcu.c | 10 ++++++--- > > drivers/net/ethernet/mediatek/mtk_wed_wo.c | 3 +++ > > 3 files changed, 26 insertions(+), 11 deletions(-) >=20 > <...> >=20 > > diff --git a/drivers/net/ethernet/mediatek/mtk_wed_mcu.c b/drivers/net/= ethernet/mediatek/mtk_wed_mcu.c > > index f9539e6233c9..b084009a32f9 100644 > > --- a/drivers/net/ethernet/mediatek/mtk_wed_mcu.c > > +++ b/drivers/net/ethernet/mediatek/mtk_wed_mcu.c > > @@ -176,6 +176,9 @@ int mtk_wed_mcu_send_msg(struct mtk_wed_wo *wo, int= id, int cmd, > > u16 seq; > > int ret; > > =20 > > + if (!wo) > > + return -ENODEV; >=20 > <...> >=20 > > static void > > mtk_wed_wo_hw_deinit(struct mtk_wed_wo *wo) > > { > > + if (!wo) > > + return; >=20 > How are these changes related to the written in deadlock? > How is it possible to get internal mtk functions without valid wo? Hi Leon, if mtk_wed_rro_alloc() fails in mtk_wed_attach(), we will end up running __mtk_wed_detach() when wo struct is not allocated yet (wo is allocated in mtk_wed_wo_init()). Moreover __mtk_wed_detach() can run mtk_wed_wo_reset() and mtk_wed_wo_deini= t() so we will need to check if wo pointer is properly set. We will face the sa= me issue if wo allocation fails in mtk_wed_wo_init routine. If we remove the deadlock we need to take into account even these condition= s. Regards, Lorenzo >=20 > Thanks >=20 > > + > > /* disable interrupts */ > > mtk_wed_wo_set_isr(wo, 0); > > =20 > > --=20 > > 2.38.1 > >=20 --FiFvvHc0xRrwB4HC Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTquNwa3Txd3rGGn7Y6cBh0uS2trAUCY4y4IQAKCRA6cBh0uS2t rNC1AP4uCyNvASYhxfjb8IiHvuONICL7rKSlK47wKTB1xSuQxAD9GoVT9OnQo2yG SFi0uEVU+b8+P96tNAvn5NUk2BqIBwU= =o4UA -----END PGP SIGNATURE----- --FiFvvHc0xRrwB4HC--