From: Alexander Usyskin alexander.usyskin@intel.com

It's not needed to set driver to NULL in mei_cl_device_remove() which is bus_type remove() handler as this is done anyway in __device_release_driver().

Actually this is causing an endless loop in driver_detach() on ubuntu patched kernel, while removing (rmmod) the mei_hdcp module. The reason list_empty(&drv->p->klist_devices.k_list) is always not-empty. as the check is always true in __device_release_driver() if (dev->driver != drv) return;

The non upstream patch is causing this behavior, titled: 'vfio -- release device lock before userspace requests'

Nevertheless the fix is correct also for the upstream.

Link: https://patchwork.ozlabs.org/project/ubuntu-kernel/patch/20180912085046.3401... Cc: stable@vger.kernel.org Cc: Andy Whitcroft apw@canonical.com Signed-off-by: Alexander Usyskin alexander.usyskin@intel.com Signed-off-by: Tomas Winkler tomas.winkler@intel.com --- drivers/misc/mei/bus.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c index 8d468e0a950a..f476dbc7252b 100644 --- a/drivers/misc/mei/bus.c +++ b/drivers/misc/mei/bus.c @@ -745,9 +745,8 @@ static int mei_cl_device_remove(struct device *dev)

mei_cl_bus_module_put(cldev); module_put(THIS_MODULE); - dev->driver = NULL; - return ret;

+ return ret; }

static ssize_t name_show(struct device *dev, struct device_attribute *a,