From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932432Ab3LQSes (ORCPT ); Tue, 17 Dec 2013 13:34:48 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:60920 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755693Ab3LQSOm (ORCPT ); Tue, 17 Dec 2013 13:14:42 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: James Bottomley , Luis Henriques Subject: [PATCH 3.5 044/103] [SCSI] enclosure: fix WARN_ON in dual path device removing Date: Tue, 17 Dec 2013 18:12:33 +0000 Message-Id: <1387304012-23805-45-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1387304012-23805-1-git-send-email-luis.henriques@canonical.com> References: <1387304012-23805-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.28 -stable review patch. If anyone has any objections, please let me know. ------------------ From: James Bottomley commit a1470c7bf3a4676e62e4c0fb204e339399eb5c59 upstream. Bug report from: wenxiong@linux.vnet.ibm.com The issue is happened in dual controller configuration. We got the sysfs warnings when rmmod the ipr module. enclosure_unregister() in drivers/msic/enclosure.c, call device_unregister() for each componment deivce, device_unregister() ->device_del()->kobject_del() ->sysfs_remove_dir(). In sysfs_remove_dir(), set kobj->sd = NULL. For each componment device, enclosure_component_release()->enclosure_remove_links()->sysfs_remove_link() in which checking kobj->sd again, it has been set as NULL when doing device_unregister. So we saw all these sysfs WARNING. Tested-by: wenxiong@linux.vnet.ibm.com Signed-off-by: James Bottomley Signed-off-by: Luis Henriques --- drivers/misc/enclosure.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/misc/enclosure.c b/drivers/misc/enclosure.c index 00e5fcac8..cbee842 100644 --- a/drivers/misc/enclosure.c +++ b/drivers/misc/enclosure.c @@ -198,6 +198,13 @@ static void enclosure_remove_links(struct enclosure_component *cdev) { char name[ENCLOSURE_NAME_SIZE]; + /* + * In odd circumstances, like multipath devices, something else may + * already have removed the links, so check for this condition first. + */ + if (!cdev->dev->kobj.sd) + return; + enclosure_link_name(cdev, name); sysfs_remove_link(&cdev->dev->kobj, name); sysfs_remove_link(&cdev->cdev.kobj, "device"); -- 1.8.3.2