From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B4C0B8BE0 for ; Tue, 28 Mar 2023 14:48:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3A880C433D2; Tue, 28 Mar 2023 14:48:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680014908; bh=q/1pTXt3XY+LQ5ad5ifmbQw7VSy38wY2z0ZSQZ7MTMs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tbshDomk+1pU3zsFoJpkGcMmw7h40Y5/MeJzwbxMkCEhagqSu6pbavZ38vHCUTUqd TAUArAls9Kk6NIsowxDY7DJ8xjWBAtpWtZ9Z7TTIRnO0f098pHBRkK8NvOwOnOfbwu 7tOT+zzw5IxrrTx0vJmvGVPzt8Je+h7vaCv65Co0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Anton Lundin , Eizan Miyamoto , Grant Grundler , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.2 095/240] net: asix: fix modprobe "sysfs: cannot create duplicate filename" Date: Tue, 28 Mar 2023 16:40:58 +0200 Message-Id: <20230328142623.721880933@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230328142619.643313678@linuxfoundation.org> References: <20230328142619.643313678@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Grant Grundler [ Upstream commit 8eac0095de355ee31e1b014f79f83d2cd62a2d04 ] "modprobe asix ; rmmod asix ; modprobe asix" fails with: sysfs: cannot create duplicate filename \ '/devices/virtual/mdio_bus/usb-003:004' Issue was originally reported by Anton Lundin on 2022-06-22 (link below). Chrome OS team hit the same issue in Feb, 2023 when trying to find work arounds for other issues with AX88172 devices. The use of devm_mdiobus_register() with usbnet devices results in the MDIO data being associated with the USB device. When the asix driver is unloaded, the USB device continues to exist and the corresponding "mdiobus_unregister()" is NOT called until the USB device is unplugged or unauthorized. So the next "modprobe asix" will fail because the MDIO phy sysfs attributes still exist. The 'easy' (from a design PoV) fix is to use the non-devm variants of mdiobus_* functions and explicitly manage this use in the asix_bind and asix_unbind function calls. I've not explored trying to fix usbnet initialization so devm_* stuff will work. Fixes: e532a096be0e5 ("net: usb: asix: ax88772: add phylib support") Reported-by: Anton Lundin Link: https://lore.kernel.org/netdev/20220623063649.GD23685@pengutronix.de/T/ Tested-by: Eizan Miyamoto Signed-off-by: Grant Grundler Link: https://lore.kernel.org/r/20230321170539.732147-1-grundler@chromium.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/usb/asix_devices.c | 32 +++++++++++++++++++++++++++----- 1 file changed, 27 insertions(+), 5 deletions(-) diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c index 743cbf5d662c9..f7cff58fe0449 100644 --- a/drivers/net/usb/asix_devices.c +++ b/drivers/net/usb/asix_devices.c @@ -666,8 +666,9 @@ static int asix_resume(struct usb_interface *intf) static int ax88772_init_mdio(struct usbnet *dev) { struct asix_common_private *priv = dev->driver_priv; + int ret; - priv->mdio = devm_mdiobus_alloc(&dev->udev->dev); + priv->mdio = mdiobus_alloc(); if (!priv->mdio) return -ENOMEM; @@ -679,7 +680,20 @@ static int ax88772_init_mdio(struct usbnet *dev) snprintf(priv->mdio->id, MII_BUS_ID_SIZE, "usb-%03d:%03d", dev->udev->bus->busnum, dev->udev->devnum); - return devm_mdiobus_register(&dev->udev->dev, priv->mdio); + ret = mdiobus_register(priv->mdio); + if (ret) { + netdev_err(dev->net, "Could not register MDIO bus (err %d)\n", ret); + mdiobus_free(priv->mdio); + priv->mdio = NULL; + } + + return ret; +} + +static void ax88772_mdio_unregister(struct asix_common_private *priv) +{ + mdiobus_unregister(priv->mdio); + mdiobus_free(priv->mdio); } static int ax88772_init_phy(struct usbnet *dev) @@ -896,16 +910,23 @@ static int ax88772_bind(struct usbnet *dev, struct usb_interface *intf) ret = ax88772_init_mdio(dev); if (ret) - return ret; + goto mdio_err; ret = ax88772_phylink_setup(dev); if (ret) - return ret; + goto phylink_err; ret = ax88772_init_phy(dev); if (ret) - phylink_destroy(priv->phylink); + goto initphy_err; + return 0; + +initphy_err: + phylink_destroy(priv->phylink); +phylink_err: + ax88772_mdio_unregister(priv); +mdio_err: return ret; } @@ -926,6 +947,7 @@ static void ax88772_unbind(struct usbnet *dev, struct usb_interface *intf) phylink_disconnect_phy(priv->phylink); rtnl_unlock(); phylink_destroy(priv->phylink); + ax88772_mdio_unregister(priv); asix_rx_fixup_common_free(dev->driver_priv); } -- 2.39.2