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 92296C4332F for ; Mon, 14 Feb 2022 10:11:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345806AbiBNKKy (ORCPT ); Mon, 14 Feb 2022 05:10:54 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:35458 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346103AbiBNKH0 (ORCPT ); Mon, 14 Feb 2022 05:07:26 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2999C75C00; Mon, 14 Feb 2022 01:50:03 -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 dfw.source.kernel.org (Postfix) with ESMTPS id B87B761284; Mon, 14 Feb 2022 09:50:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9E69CC340E9; Mon, 14 Feb 2022 09:50:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1644832202; bh=HeaVS8YJXYExBvHJjvzB8Zo18vyuqr4/tONb6YB89pU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ViL9Q97CG3kctPeYrLMFmyP/jeSTlUQ+uKJNac+sWw64eqSzuOdXVEzcZ/FdN6V/T nkwW+zLNHEY4zQz7KtEyGRU0DwnVl5YBbzi5SAE4cxmrA2FsV5mOOOP/88B52eSXUU jh32mgeMq/zWDKdbi9reI1j7JXnxi9QivGP8hNSw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vladimir Oltean , Florian Fainelli , Oleksij Rempel , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15 112/172] net: dsa: ar9331: register the mdiobus under devres Date: Mon, 14 Feb 2022 10:26:10 +0100 Message-Id: <20220214092510.298066364@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220214092506.354292783@linuxfoundation.org> References: <20220214092506.354292783@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 50facd86e9fbc4b93fe02e5fe05776047f45dbfb ] 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 ar9331 is an MDIO 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 ar9331 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 ar9331 driver doesn't have a complex code structure for mdiobus removal, so just replace of_mdiobus_register with the devres variant in order to be all-devres and ensure that we don't 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 Tested-by: Oleksij Rempel Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/dsa/qca/ar9331.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/net/dsa/qca/ar9331.c b/drivers/net/dsa/qca/ar9331.c index a6bfb6abc51a7..5d476f452396c 100644 --- a/drivers/net/dsa/qca/ar9331.c +++ b/drivers/net/dsa/qca/ar9331.c @@ -378,7 +378,7 @@ static int ar9331_sw_mbus_init(struct ar9331_sw_priv *priv) if (!mnp) return -ENODEV; - ret = of_mdiobus_register(mbus, mnp); + ret = devm_of_mdiobus_register(dev, mbus, mnp); of_node_put(mnp); if (ret) return ret; @@ -1093,7 +1093,6 @@ static void ar9331_sw_remove(struct mdio_device *mdiodev) } irq_domain_remove(priv->irqdomain); - mdiobus_unregister(priv->mbus); dsa_unregister_switch(&priv->ds); reset_control_assert(priv->sw_reset); -- 2.34.1