path: root/drivers/uwb
diff options
authorThomas Pugliese <thomas.pugliese@gmail.com>2013-12-20 13:01:03 -0600
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-12-20 12:19:44 -0800
commit1fc671b3be8f671482871d9a0b577b6d96914e8e (patch)
tree09232d31e58b5ffad10dbc560db4d8fad45badab /drivers/uwb
parentbf359dff2346d490dbbbe0fcc4aa674625803da5 (diff)
uwb: move mutex_lock to error case in uwbd_evt_handle_rc_bp_slot_change
Only acquire rc->uwb_dev.mutex in the error case in uwbd_evt_handle_rc_bp_slot_change. This fixes a bug where establishing a reservation on a new channel will fail if we were unable to establish a reservation on the previous channel due to DRP conflict. If rc->uwb_dev.mutex is acquired in the non-error case when the uwb system is attempting to start beaconing, it will block because the start beaconing code is holding this mutex. This prevents any other notifications from the URC from being processed. In particular, the DRP_AVAILABILITY notification will not be processed during the start beaconing process which can result in a failure to establish a reservation. It is safe to not hold the mutex in the non-error case since the only other place rc->uwb_dev.beacon_slot is accessed is in the same worker thread that uwbd_evt_handle_rc_bp_slot_change executes in. Signed-off-by: Thomas Pugliese <thomas.pugliese@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/uwb')
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/uwb/beacon.c b/drivers/uwb/beacon.c
index 4190f29fe312..57b5ff61020c 100644
--- a/drivers/uwb/beacon.c
+++ b/drivers/uwb/beacon.c
@@ -516,13 +516,13 @@ int uwbd_evt_handle_rc_bp_slot_change(struct uwb_event *evt)
bpsc = container_of(evt->notif.rceb, struct uwb_rc_evt_bp_slot_change, rceb);
- mutex_lock(&rc->uwb_dev.mutex);
if (uwb_rc_evt_bp_slot_change_no_slot(bpsc)) {
dev_err(dev, "stopped beaconing: No free slots in BP\n");
+ mutex_lock(&rc->uwb_dev.mutex);
rc->beaconing = -1;
+ mutex_unlock(&rc->uwb_dev.mutex);
} else
rc->uwb_dev.beacon_slot = uwb_rc_evt_bp_slot_change_slot_num(bpsc);
- mutex_unlock(&rc->uwb_dev.mutex);
return 0;

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