Re: [PATCH v2] drm/display: fix MST branch device refcount leak on DPCD write failure

[Greg KH]

On Sun, Jun 28, 2026 at 09:33:44PM +0800, WenTao Liang wrote:
> drm_dp_add_mst_branch_device initializes mstb with refcount 1, and
> drm_dp_mst_topology_get_mstb increments it to 2. When
> drm_dp_dpcd_write_byte fails, out_unlock performs only one
> drm_dp_mst_topology_put_mstb, leaving the other reference stored in
> mgr->mst_primary. Since MST was not successfully enabled, no disable path
> will clean it up.
> 
> Suggested-by: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>

I did?  Where did I do that?

> Fixes: 7a3cbf590e63 ("drm/mst: Some style improvements in drm_dp_mst_topology_mgr_set_mst()")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: WenTao Liang <vulab@xxxxxxxxxxx>

Again, you need to document the tools you used to find/fix this with
assisted-by, right?  Please read our documentation for when you use
LLMs.

thanks,

greg k-h