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 X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F934C433F5 for ; Mon, 3 Sep 2018 17:01:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1463820862 for ; Mon, 3 Sep 2018 17:01:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1463820862 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728706AbeICVWd (ORCPT ); Mon, 3 Sep 2018 17:22:33 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:38714 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727977AbeICVWd (ORCPT ); Mon, 3 Sep 2018 17:22:33 -0400 Received: from localhost (ip-213-127-74-90.ip.prioritytelecom.net [213.127.74.90]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 7DC59CFC; Mon, 3 Sep 2018 17:01:33 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Shubhrajyoti Datta , "David S. Miller" , Sasha Levin Subject: [PATCH 4.4 26/80] net: axienet: Fix double deregister of mdio Date: Mon, 3 Sep 2018 18:49:04 +0200 Message-Id: <20180903164935.198355094@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180903164934.171677301@linuxfoundation.org> References: <20180903164934.171677301@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Shubhrajyoti Datta [ Upstream commit 03bc7cab7d7218088412a75e141696a89059ab00 ] If the registration fails then mdio_unregister is called. However at unbind the unregister ia attempted again resulting in the below crash [ 73.544038] kernel BUG at drivers/net/phy/mdio_bus.c:415! [ 73.549362] Internal error: Oops - BUG: 0 [#1] SMP [ 73.554127] Modules linked in: [ 73.557168] CPU: 0 PID: 2249 Comm: sh Not tainted 4.14.0 #183 [ 73.562895] Hardware name: xlnx,zynqmp (DT) [ 73.567062] task: ffffffc879e41180 task.stack: ffffff800cbe0000 [ 73.572973] PC is at mdiobus_unregister+0x84/0x88 [ 73.577656] LR is at axienet_mdio_teardown+0x18/0x30 [ 73.582601] pc : [] lr : [] pstate: 20000145 [ 73.589981] sp : ffffff800cbe3c30 [ 73.593277] x29: ffffff800cbe3c30 x28: ffffffc879e41180 [ 73.598573] x27: ffffff8008a21000 x26: 0000000000000040 [ 73.603868] x25: 0000000000000124 x24: ffffffc879efe920 [ 73.609164] x23: 0000000000000060 x22: ffffffc879e02000 [ 73.614459] x21: ffffffc879e02800 x20: ffffffc87b0b8870 [ 73.619754] x19: ffffffc879e02800 x18: 000000000000025d [ 73.625050] x17: 0000007f9a719ad0 x16: ffffff8008195bd8 [ 73.630345] x15: 0000007f9a6b3d00 x14: 0000000000000010 [ 73.635640] x13: 74656e7265687465 x12: 0000000000000030 [ 73.640935] x11: 0000000000000030 x10: 0101010101010101 [ 73.646231] x9 : 241f394f42533300 x8 : ffffffc8799f6e98 [ 73.651526] x7 : ffffffc8799f6f18 x6 : ffffffc87b0ba318 [ 73.656822] x5 : ffffffc87b0ba498 x4 : 0000000000000000 [ 73.662117] x3 : 0000000000000000 x2 : 0000000000000008 [ 73.667412] x1 : 0000000000000004 x0 : ffffffc8799f4000 [ 73.672708] Process sh (pid: 2249, stack limit = 0xffffff800cbe0000) Fix the same by making the bus NULL on unregister. Signed-off-by: Shubhrajyoti Datta Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c @@ -218,6 +218,7 @@ issue: ret = of_mdiobus_register(bus, np1); if (ret) { mdiobus_free(bus); + lp->mii_bus = NULL; return ret; } return 0;