edac: core fix to use dynamic kobject
Static kobjects are not supported in linux kernel. Convert the
edac_pci_top_main_kobj from static to dynamic. This avoids the double
free of the edac_pci_top_main_kobj.name that we see on module reload of
the e752x edac driver (and probably others as well).
In addition Greg KH <greg@kroah.com> has pointed out that this code may be
cleaned up significantly. I will look at that as a follow-on patch, for
now, I just want the minimum fix to get this double-free oops bug
squashed...
Many thanks to Greg KH for his patience in showing me what the
Documentation/kobject.txt already said (oops)...
Signed-off-by: Arthur Jones <ajones@riverbed.com>
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/edac/edac_pci_sysfs.c b/drivers/edac/edac_pci_sysfs.c
index 2c1fa1b..5c153dc 100644
--- a/drivers/edac/edac_pci_sysfs.c
+++ b/drivers/edac/edac_pci_sysfs.c
@@ -28,7 +28,7 @@
static atomic_t pci_parity_count = ATOMIC_INIT(0);
static atomic_t pci_nonparity_count = ATOMIC_INIT(0);
-static struct kobject edac_pci_top_main_kobj;
+static struct kobject *edac_pci_top_main_kobj;
static atomic_t edac_pci_sysfs_refcount = ATOMIC_INIT(0);
/* getter functions for the data variables */
@@ -83,7 +83,7 @@
pci = to_instance(kobj);
/* decrement reference count on top main kobj */
- kobject_put(&edac_pci_top_main_kobj);
+ kobject_put(edac_pci_top_main_kobj);
kfree(pci); /* Free the control struct */
}
@@ -166,7 +166,7 @@
* track the number of PCI instances we have, and thus nest
* properly on keeping the module loaded
*/
- main_kobj = kobject_get(&edac_pci_top_main_kobj);
+ main_kobj = kobject_get(edac_pci_top_main_kobj);
if (!main_kobj) {
err = -ENODEV;
goto error_out;
@@ -174,11 +174,11 @@
/* And now register this new kobject under the main kobj */
err = kobject_init_and_add(&pci->kobj, &ktype_pci_instance,
- &edac_pci_top_main_kobj, "pci%d", idx);
+ edac_pci_top_main_kobj, "pci%d", idx);
if (err != 0) {
debugf2("%s() failed to register instance pci%d\n",
__func__, idx);
- kobject_put(&edac_pci_top_main_kobj);
+ kobject_put(edac_pci_top_main_kobj);
goto error_out;
}
@@ -316,9 +316,10 @@
*/
static void edac_pci_release_main_kobj(struct kobject *kobj)
{
-
debugf0("%s() here to module_put(THIS_MODULE)\n", __func__);
+ kfree(kobj);
+
/* last reference to top EDAC PCI kobject has been removed,
* NOW release our ref count on the core module
*/
@@ -369,8 +370,16 @@
goto decrement_count_fail;
}
+ edac_pci_top_main_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
+ if (!edac_pci_top_main_kobj) {
+ debugf1("Failed to allocate\n");
+ err = -ENOMEM;
+ goto kzalloc_fail;
+ }
+
/* Instanstiate the pci object */
- err = kobject_init_and_add(&edac_pci_top_main_kobj, &ktype_edac_pci_main_kobj,
+ err = kobject_init_and_add(edac_pci_top_main_kobj,
+ &ktype_edac_pci_main_kobj,
&edac_class->kset.kobj, "pci");
if (err) {
debugf1("Failed to register '.../edac/pci'\n");
@@ -381,13 +390,16 @@
* for EDAC PCI, then edac_pci_main_kobj_teardown()
* must be used, for resources to be cleaned up properly
*/
- kobject_uevent(&edac_pci_top_main_kobj, KOBJ_ADD);
+ kobject_uevent(edac_pci_top_main_kobj, KOBJ_ADD);
debugf1("Registered '.../edac/pci' kobject\n");
return 0;
/* Error unwind statck */
kobject_init_and_add_fail:
+ kfree(edac_pci_top_main_kobj);
+
+kzalloc_fail:
module_put(THIS_MODULE);
decrement_count_fail:
@@ -414,7 +426,7 @@
if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) {
debugf0("%s() called kobject_put on main kobj\n",
__func__);
- kobject_put(&edac_pci_top_main_kobj);
+ kobject_put(edac_pci_top_main_kobj);
}
}