SCSI: enclosure: fix WARN_ON in dual path device removing
authorJames Bottomley <JBottomley@Parallels.com>
Fri, 15 Nov 2013 22:58:00 +0000 (14:58 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 12 Dec 2013 06:36:27 +0000 (22:36 -0800)
commite891b8e307009b44fa1e70a49a59e8db6cbe12fa
tree2dd8293a889b4e4c974a286c429e56ca18c4c1e0
parentf8ce2dfb243bedc9113a722ae3614c6f33791923
SCSI: enclosure: fix WARN_ON in dual path device removing

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 <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/misc/enclosure.c