In function mei_nfc_host_exit mei_cl_remove_device cannot be called
under the device mutex as device removing flow invokes the device driver
remove handler that calls in turn to mei_cl_disable_device which
naturally acquires the device mutex.

Also remove mei_cl_bus_remove_devices which has the same issue, but is
never executed as currently the only device on the mei client bus is
NFC and a new device cannot be easily added till
the bus revamp is completed.

This fixes regression caused by commit
be9b720a0ccba096d669bc86634f900b82b9bf71
Author: Tomas Winkler <tomas.wink...@intel.com>
Date:   Thu May 7 15:54:04 2015 +0300
NFC: mei_phy: move all nfc logic from mei driver to nfc

Prior to this change the nfc driver remove handler
called to no-op disable function while actual nfc
device was disabled directly from the mei driver.

Reported-by: Linus Torvalds <torva...@linux-foundation.org>
Cc: Samuel Ortiz <sa...@linux.intel.com>
Signed-off-by: Tomas Winkler <tomas.wink...@intel.com>
---
 drivers/misc/mei/bus.c  | 16 ----------------
 drivers/misc/mei/init.c |  2 --
 drivers/misc/mei/nfc.c  |  3 ++-
 3 files changed, 2 insertions(+), 19 deletions(-)

diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
index 357b6ae4d207..458aa5a09c52 100644
--- a/drivers/misc/mei/bus.c
+++ b/drivers/misc/mei/bus.c
@@ -552,22 +552,6 @@ void mei_cl_bus_rx_event(struct mei_cl *cl)
        schedule_work(&device->event_work);
 }
 
-void mei_cl_bus_remove_devices(struct mei_device *dev)
-{
-       struct mei_cl *cl, *next;
-
-       mutex_lock(&dev->device_lock);
-       list_for_each_entry_safe(cl, next, &dev->device_list, device_link) {
-               if (cl->device)
-                       mei_cl_remove_device(cl->device);
-
-               list_del(&cl->device_link);
-               mei_cl_unlink(cl);
-               kfree(cl);
-       }
-       mutex_unlock(&dev->device_lock);
-}
-
 int __init mei_cl_bus_init(void)
 {
        return bus_register(&mei_cl_bus_type);
diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c
index 94514b2c7a50..00c3865ca3b1 100644
--- a/drivers/misc/mei/init.c
+++ b/drivers/misc/mei/init.c
@@ -333,8 +333,6 @@ void mei_stop(struct mei_device *dev)
 
        mei_nfc_host_exit(dev);
 
-       mei_cl_bus_remove_devices(dev);
-
        mutex_lock(&dev->device_lock);
 
        mei_wd_stop(dev);
diff --git a/drivers/misc/mei/nfc.c b/drivers/misc/mei/nfc.c
index b983c4ecad38..290ef3037437 100644
--- a/drivers/misc/mei/nfc.c
+++ b/drivers/misc/mei/nfc.c
@@ -402,11 +402,12 @@ void mei_nfc_host_exit(struct mei_device *dev)
 
        cldev->priv_data = NULL;
 
-       mutex_lock(&dev->device_lock);
        /* Need to remove the device here
         * since mei_nfc_free will unlink the clients
         */
        mei_cl_remove_device(cldev);
+
+       mutex_lock(&dev->device_lock);
        mei_nfc_free(ndev);
        mutex_unlock(&dev->device_lock);
 }
-- 
2.4.3

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