Hi Zeng,
In the future, please do not send a new version of a patch series as a reply
to a previous thread. For people who leave threads collapsed in their email
client (like me), there is a good chance that the new patch version email
will not be noticed.
More below...
On 11/20/22 21:53, Zeng Heng wrote:
> When of_changeset_attach_node() returns fail and tchild is
> over of life cycle which is duplicated by __of_node_dup(),
> it needs to call of_node_put() to release tchild in
> error handle route.
This does not seem correct. I will explain this in the patch v1
thread.
>
> Otherwise, there are some memory leak reported about the node:
>
> unreferenced object 0xffff88810cd1e800 (size 256):
> backtrace:
> kmalloc_trace
> __of_node_dup
> add_changeset_node (inlined)
> build_changeset_next_level
>
> unreferenced object 0xffff888113721240 (size 16):
> backtrace:
> __kmalloc_node_track_caller
> kstrdup
> __of_node_dup
> add_changeset_node (inlined)
> build_changeset_next_level
>
> unreferenced object 0xffff88810a38d400 (size 128):
> backtrace:
> kmalloc_trace
> __of_prop_dup
> add_changeset_property
> build_changeset_next_level
>
> Fixes: 0290c4ca2536 ("of: overlay: rename identifiers to more reflect what they do")
You have to dig deeper. The code that introduced the issue is even older:
7518b5890d8a of/overlay: Introduce DT overlay support
-Frank
> Signed-off-by: Zeng Heng <zengheng4@xxxxxxxxxx>
> ---
> drivers/of/overlay.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
> index bd8ff4df723d..a5189a0ec0a3 100644
> --- a/drivers/of/overlay.c
> +++ b/drivers/of/overlay.c
> @@ -436,8 +436,10 @@ static int add_changeset_node(struct overlay_changeset *ovcs,
> of_node_set_flag(tchild, OF_OVERLAY);
>
> ret = of_changeset_attach_node(&ovcs->cset, tchild);
> - if (ret)
> + if (ret) {
> + of_node_put(tchild);
> return ret;
> + }
>
> target_child.np = tchild;
> target_child.in_livetree = false;
