edac_core: Do a better job with node removal

Make sure we remove groups at the right order
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/edac/edac_mc.c

@@ -207,6 +207,7 @@ struct mem_ctl_info *edac_mc_alloc(unsigned sz_pvt, unsigned nr_csrows,
 	}
 
 	mci->op_state = OP_ALLOC;
+	INIT_LIST_HEAD(&mci->grp_kobj_list);
 
 	/*
 	 * Initialize the 'root' kobj for the edac_mc controller

drivers/edac/edac_mc_sysfs.c

@@ -791,6 +791,7 @@ static int edac_create_mci_instance_attributes(struct mem_ctl_info *mci,
 	debugf1("%s()\n", __func__);
 
 	while (sysfs_attrib) {
+		debugf1("%s() sysfs_attrib = %p\n",__func__, sysfs_attrib);
 		if (sysfs_attrib->grp) {
 			struct mcidev_sysfs_group_kobj *grp_kobj;
 
@@ -798,10 +799,9 @@ static int edac_create_mci_instance_attributes(struct mem_ctl_info *mci,
 			if (!grp_kobj)
 				return -ENOMEM;
 
-			list_add_tail(&grp_kobj->list, &mci->grp_kobj_list);
-
 			grp_kobj->grp = sysfs_attrib->grp;
 			grp_kobj->mci = mci;
+			list_add_tail(&grp_kobj->list, &mci->grp_kobj_list);
 
 			debugf0("%s() grp %s, mci %p\n", __func__,
 				sysfs_attrib->grp->name, mci);
@@ -810,26 +810,28 @@ static int edac_create_mci_instance_attributes(struct mem_ctl_info *mci,
 						&ktype_inst_grp,
 						&mci->edac_mci_kobj,
 						sysfs_attrib->grp->name);
-			if (err)
+			if (err < 0) {
+				printk(KERN_ERR "kobject_init_and_add failed: %d\n", err);
 				return err;
-
+			}
 			err = edac_create_mci_instance_attributes(mci,
 					grp_kobj->grp->mcidev_attr,
 					&grp_kobj->kobj);
 
-			if (err)
+			if (err < 0)
 				return err;
 		} else if (sysfs_attrib->attr.name) {
 			debugf0("%s() file %s\n", __func__,
 				sysfs_attrib->attr.name);
 
 			err = sysfs_create_file(kobj, &sysfs_attrib->attr);
+			if (err < 0) {
+				printk(KERN_ERR "sysfs_create_file failed: %d\n", err);
+				return err;
+			}
 		} else
 			break;
 
-		if (err) {
-			return err;
-		}
 		sysfs_attrib++;
 	}
 
@@ -854,13 +856,24 @@ static void edac_remove_mci_instance_attributes(struct mem_ctl_info *mci,
 	 * Remove first all the atributes
 	 */
 	while (sysfs_attrib) {
+		debugf1("%s() sysfs_attrib = %p\n",__func__, sysfs_attrib);
 		if (sysfs_attrib->grp) {
-			list_for_each_entry(grp_kobj, &mci->grp_kobj_list,
-					    list)
-				if (grp_kobj->grp == sysfs_attrib->grp)
+			debugf1("%s() seeking for group %s\n",
+				__func__, sysfs_attrib->grp->name);
+			list_for_each_entry(grp_kobj,
+					    &mci->grp_kobj_list, list) {
+				debugf1("%s() grp_kobj->grp = %p\n",__func__, grp_kobj->grp);
+				if (grp_kobj->grp == sysfs_attrib->grp) {
 					edac_remove_mci_instance_attributes(mci,
 						    grp_kobj->grp->mcidev_attr,
 						    &grp_kobj->kobj, count + 1);
+					debugf0("%s() group %s\n", __func__,
+						sysfs_attrib->grp->name);
+					kobject_put(&grp_kobj->kobj);
+				}
+			}
+			debugf1("%s() end of seeking for group %s\n",
+				__func__, sysfs_attrib->grp->name);
 		} else if (sysfs_attrib->attr.name) {
 			debugf0("%s() file %s\n", __func__,
 				sysfs_attrib->attr.name);
@@ -870,14 +883,13 @@ static void edac_remove_mci_instance_attributes(struct mem_ctl_info *mci,
 		sysfs_attrib++;
 	}
 
-	/*
-	 * Now that all attributes got removed, it is save to remove all groups
-	 */
-	if (!count)
-		list_for_each_entry_safe(grp_kobj, tmp, &mci->grp_kobj_list,
-					 list) {
-			debugf0("%s() grp %s\n", __func__, grp_kobj->grp->name);
-			kobject_put(&grp_kobj->kobj);
+	/* Remove the group objects */
+	if (count)
+		return;
+	list_for_each_entry_safe(grp_kobj, tmp,
+				 &mci->grp_kobj_list, list) {
+		list_del(&grp_kobj->list);
+		kfree(grp_kobj);
 	}
 }
 
@@ -970,6 +982,7 @@ void edac_remove_sysfs_mci_device(struct mem_ctl_info *mci)
 	debugf0("%s()\n", __func__);
 
 	/* remove all csrow kobjects */
+	debugf0("%s()  unregister this mci kobj\n", __func__);
 	for (i = 0; i < mci->nr_csrows; i++) {
 		if (mci->csrows[i].nr_pages > 0) {
 			debugf0("%s()  unreg csrow-%d\n", __func__, i);
@@ -977,20 +990,20 @@ void edac_remove_sysfs_mci_device(struct mem_ctl_info *mci)
 		}
 	}
 
-	debugf0("%s()  remove_link\n", __func__);
-
-	/* remove the symlink */
-	sysfs_remove_link(&mci->edac_mci_kobj, EDAC_DEVICE_SYMLINK);
-
-	debugf0("%s()  remove_mci_instance\n", __func__);
-
 	/* remove this mci instance's attribtes */
+	if (mci->mc_driver_sysfs_attributes) {
+		debugf0("%s()  unregister mci private attributes\n", __func__);
 		edac_remove_mci_instance_attributes(mci,
 						mci->mc_driver_sysfs_attributes,
 						&mci->edac_mci_kobj, 0);
-	debugf0("%s()  unregister this mci kobj\n", __func__);
+	}
+
+	/* remove the symlink */
+	debugf0("%s()  remove_link\n", __func__);
+	sysfs_remove_link(&mci->edac_mci_kobj, EDAC_DEVICE_SYMLINK);
 
 	/* unregister this instance's kobject */
+	debugf0("%s()  remove_mci_instance\n", __func__);
 	kobject_put(&mci->edac_mci_kobj);
 }