From akpm@linux-foundation.org Wed Feb 21 12:45:48 2007
Date: Wed, 21 Feb 2007 12:45:35 -0800
From: Mike Galbraith <efault@gmx.de>
Subject: driver core: refcounting fix
To: mm-commits@vger.kernel.org
Cc: efault@gmx.de, greg@kroah.com
Message-ID: <200702212045.l1LKjZCs025361@shell0.pdx.osdl.net>

From: Mike Galbraith <efault@gmx.de>

Fix a reference counting bug exposed by commit
725522b5453dd680412f2b6463a988e4fd148757.  If driver.mod_name exists, we
take a reference in module_add_driver(), and never release it.  Undo that
reference in module_remove_driver().

Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>


---
 kernel/module.c |    6 ++++++
 1 file changed, 6 insertions(+)

--- gregkh-2.6.orig/kernel/module.c
+++ gregkh-2.6/kernel/module.c
@@ -2425,6 +2425,12 @@ void module_remove_driver(struct device_
 			kfree(driver_name);
 		}
 	}
+	/*
+	 * Undo the additional reference we added in module_add_driver()
+	 * via kset_find_obj()
+	 */
+	if (drv->mod_name)
+		kobject_put(&drv->kobj);
 }
 EXPORT_SYMBOL(module_remove_driver);
 #endif