aboutsummaryrefslogtreecommitdiff
path: root/drivers/of/dynamic.c
diff options
context:
space:
mode:
authorFrank Rowand <frank.rowand@sony.com>2018-10-04 20:24:17 -0700
committerFrank Rowand <frank.rowand@sony.com>2018-11-08 22:10:35 -0800
commit144552c786925314c1e7cb8f91a71dae1aca8798 (patch)
tree529691048e02c625ece39d41db6304f6f16db9a9 /drivers/of/dynamic.c
parent651022382c7f8da46cb4872a545ee1da6d097d2a (diff)
downloadlinux-stericsson-144552c786925314c1e7cb8f91a71dae1aca8798.tar.gz
of: overlay: add tests to validate kfrees from overlay removal
Add checks: - attempted kfree due to refcount reaching zero before overlay is removed - properties linked to an overlay node when the node is removed - node refcount > one during node removal in a changeset destroy, if the node was created by the changeset After applying this patch, several validation warnings will be reported from the devicetree unittest during boot due to pre-existing devicetree bugs. The warnings will be similar to: OF: ERROR: of_node_release(), unexpected properties in /testcase-data/overlay-node/test-bus/test-unittest11 OF: ERROR: memory leak, expected refcount 1 instead of 2, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /testcase-data-2/substation@100/ hvac-medium-2 Tested-by: Alan Tull <atull@kernel.org> Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Diffstat (limited to 'drivers/of/dynamic.c')
-rw-r--r--drivers/of/dynamic.c29
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index f4f8ed9b5454..12c3f9a15e94 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -330,6 +330,25 @@ void of_node_release(struct kobject *kobj)
if (!of_node_check_flag(node, OF_DYNAMIC))
return;
+ if (of_node_check_flag(node, OF_OVERLAY)) {
+
+ if (!of_node_check_flag(node, OF_OVERLAY_FREE_CSET)) {
+ /* premature refcount of zero, do not free memory */
+ pr_err("ERROR: memory leak before free overlay changeset, %pOF\n",
+ node);
+ return;
+ }
+
+ /*
+ * If node->properties non-empty then properties were added
+ * to this node either by different overlay that has not
+ * yet been removed, or by a non-overlay mechanism.
+ */
+ if (node->properties)
+ pr_err("ERROR: %s(), unexpected properties in %pOF\n",
+ __func__, node);
+ }
+
property_list_free(node->properties);
property_list_free(node->deadprops);
@@ -434,6 +453,16 @@ struct device_node *__of_node_dup(const struct device_node *np,
static void __of_changeset_entry_destroy(struct of_changeset_entry *ce)
{
+ if (ce->action == OF_RECONFIG_ATTACH_NODE &&
+ of_node_check_flag(ce->np, OF_OVERLAY)) {
+ if (kref_read(&ce->np->kobj.kref) > 1) {
+ pr_err("ERROR: memory leak, expected refcount 1 instead of %d, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node %pOF\n",
+ kref_read(&ce->np->kobj.kref), ce->np);
+ } else {
+ of_node_set_flag(ce->np, OF_OVERLAY_FREE_CSET);
+ }
+ }
+
of_node_put(ce->np);
list_del(&ce->node);
kfree(ce);