From patchwork Wed Jul 22 12:38:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Claudiu Manoil X-Patchwork-Id: 1333871 Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=nxp.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4BBZkb0y1gz9sR4 for ; Wed, 22 Jul 2020 22:38:15 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731695AbgGVMiL (ORCPT ); Wed, 22 Jul 2020 08:38:11 -0400 Received: from inva020.nxp.com ([92.121.34.13]:50306 "EHLO inva020.nxp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726161AbgGVMiK (ORCPT ); Wed, 22 Jul 2020 08:38:10 -0400 Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 6CC211A0A7D; Wed, 22 Jul 2020 14:38:08 +0200 (CEST) Received: from inva024.eu-rdc02.nxp.com (inva024.eu-rdc02.nxp.com [134.27.226.22]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 60A601A0A6A; Wed, 22 Jul 2020 14:38:08 +0200 (CEST) Received: from fsr-ub1664-016.ea.freescale.net (fsr-ub1664-016.ea.freescale.net [10.171.71.216]) by inva024.eu-rdc02.nxp.com (Postfix) with ESMTP id 3B34C202AD; Wed, 22 Jul 2020 14:38:08 +0200 (CEST) From: Claudiu Manoil To: "David S . Miller" Cc: netdev@vger.kernel.org Subject: [PATCH net] enetc: Remove the mdio bus on PF probe bailout Date: Wed, 22 Jul 2020 15:38:07 +0300 Message-Id: <1595421487-13978-1-git-send-email-claudiu.manoil@nxp.com> X-Mailer: git-send-email 2.7.4 X-Virus-Scanned: ClamAV using ClamSMTP Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org For ENETC ports that register an external MDIO bus, the bus doesn't get removed on the error bailout path of enetc_pf_probe(). Fix this by unregistering the bus inside enetc_of_put_phy(), since enetc_of_get_phy() is were it gets registered. This issue became much more visible after recent: commit 07095c025ac2 ("net: enetc: Use DT protocol information to set up the ports") Before this commit, one could make probing fail on the error path only by having register_netdev() fail, which is unlikely. But after this commit, because it moved the enetc_of_phy_get() call up in the probing sequence, now we can trigger an mdiobus_free() bug just by forcing enetc_alloc_msix() to return error, i.e. with the 'pci=nomsi' kernel bootarg (since ENETC relies on MSI support to work), as the calltrace below shows: kernel BUG at /home/eiz/work/enetc/net/drivers/net/phy/mdio_bus.c:648! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [...] Hardware name: LS1028A RDB Board (DT) pstate: 80000005 (Nzcv daif -PAN -UAO BTYPE=--) pc : mdiobus_free+0x50/0x58 lr : devm_mdiobus_free+0x14/0x20 [...] Call trace: mdiobus_free+0x50/0x58 devm_mdiobus_free+0x14/0x20 release_nodes+0x138/0x228 devres_release_all+0x38/0x60 really_probe+0x1c8/0x368 driver_probe_device+0x5c/0xc0 device_driver_attach+0x74/0x80 __driver_attach+0x8c/0xd8 bus_for_each_dev+0x7c/0xd8 driver_attach+0x24/0x30 bus_add_driver+0x154/0x200 driver_register+0x64/0x120 __pci_register_driver+0x44/0x50 enetc_pf_driver_init+0x24/0x30 do_one_initcall+0x60/0x1c0 kernel_init_freeable+0x1fc/0x274 kernel_init+0x14/0x110 ret_from_fork+0x10/0x34 Fixes: ebfcb23d62ab ("enetc: Add ENETC PF level external MDIO support") Signed-off-by: Claudiu Manoil --- drivers/net/ethernet/freescale/enetc/enetc_pf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c index 4fac57dbb3c8..bd42732f1375 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c +++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c @@ -827,6 +827,7 @@ static void enetc_of_put_phy(struct enetc_ndev_priv *priv) { struct device_node *np = priv->dev->of_node; + enetc_mdio_remove(pf); if (np && of_phy_is_fixed_link(np)) of_phy_deregister_fixed_link(np); if (priv->phy_node) @@ -932,7 +933,6 @@ static void enetc_pf_remove(struct pci_dev *pdev) priv = netdev_priv(si->ndev); unregister_netdev(si->ndev); - enetc_mdio_remove(pf); enetc_of_put_phy(priv); enetc_free_msix(priv);