From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE42BC433F5 for ; Mon, 14 Feb 2022 10:34:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348251AbiBNKe0 (ORCPT ); Mon, 14 Feb 2022 05:34:26 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:43734 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347736AbiBNKdW (ORCPT ); Mon, 14 Feb 2022 05:33:22 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7EC4DA1BCB; Mon, 14 Feb 2022 02:00:34 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 7BF56B80DBE; Mon, 14 Feb 2022 10:00:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 668E0C340E9; Mon, 14 Feb 2022 10:00:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1644832831; bh=RqmcDVCintIL4s3Ge1wQ9SsymjEA67HDOlmb4mXgUhY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GAl4lis0TIfKQnk2UZEccmV1c31JO0GIMEf7iPEt7AQcV/GBzmbIgD8SN4bOEuHJk sMzjTYO+Z9eIKFOqu2/RLruRYT5W5pYRYY3l8HSxgUuRdvW4O+tCKisa1hQCTeqKY4 C1XROpI3p//vmbOzMxoKDDZZTkjpIcAI31X2rHD4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vladimir Oltean , Florian Fainelli , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.16 137/203] net: dsa: felix: dont use devres for mdiobus Date: Mon, 14 Feb 2022 10:26:21 +0100 Message-Id: <20220214092514.888425741@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220214092510.221474733@linuxfoundation.org> References: <20220214092510.221474733@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vladimir Oltean [ Upstream commit 209bdb7ec6a28c7cdf580a0a98afbc9fc3b98932 ] As explained in commits: 74b6d7d13307 ("net: dsa: realtek: register the MDIO bus under devres") 5135e96a3dd2 ("net: dsa: don't allocate the slave_mii_bus using devres") mdiobus_free() will panic when called from devm_mdiobus_free() <- devres_release_all() <- __device_release_driver(), and that mdiobus was not previously unregistered. The Felix VSC9959 switch is a PCI device, so the initial set of constraints that I thought would cause this (I2C or SPI buses which call ->remove on ->shutdown) do not apply. But there is one more which applies here. If the DSA master itself is on a bus that calls ->remove from ->shutdown (like dpaa2-eth, which is on the fsl-mc bus), there is a device link between the switch and the DSA master, and device_links_unbind_consumers() will unbind the felix switch driver on shutdown. So the same treatment must be applied to all DSA switch drivers, which is: either use devres for both the mdiobus allocation and registration, or don't use devres at all. The felix driver has the code structure in place for orderly mdiobus removal, so just replace devm_mdiobus_alloc_size() with the non-devres variant, and add manual free where necessary, to ensure that we don't let devres free a still-registered bus. Fixes: ac3a68d56651 ("net: phy: don't abuse devres in devm_mdiobus_register()") Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/dsa/ocelot/felix_vsc9959.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/dsa/ocelot/felix_vsc9959.c b/drivers/net/dsa/ocelot/felix_vsc9959.c index 45c5ec7a83eaf..12c2acbc2427b 100644 --- a/drivers/net/dsa/ocelot/felix_vsc9959.c +++ b/drivers/net/dsa/ocelot/felix_vsc9959.c @@ -1064,7 +1064,7 @@ static int vsc9959_mdio_bus_alloc(struct ocelot *ocelot) return PTR_ERR(hw); } - bus = devm_mdiobus_alloc_size(dev, sizeof(*mdio_priv)); + bus = mdiobus_alloc_size(sizeof(*mdio_priv)); if (!bus) return -ENOMEM; @@ -1084,6 +1084,7 @@ static int vsc9959_mdio_bus_alloc(struct ocelot *ocelot) rc = mdiobus_register(bus); if (rc < 0) { dev_err(dev, "failed to register MDIO bus\n"); + mdiobus_free(bus); return rc; } @@ -1133,6 +1134,7 @@ static void vsc9959_mdio_bus_free(struct ocelot *ocelot) lynx_pcs_destroy(pcs); } mdiobus_unregister(felix->imdio); + mdiobus_free(felix->imdio); } static void vsc9959_sched_speed_set(struct ocelot *ocelot, int port, -- 2.34.1