IB/ucm: Fix bitmap wrap when devnum > IB_UCM_MAX_DEVICES

ib_ucm_release_dev clears the wrong bit if devnum is greater
than IB_UCM_MAX_DEVICES.

Signed-off-by: Carol L Soto <clsoto@linux.vnet.ibm.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/core/ucm.c b/drivers/infiniband/core/ucm.c
index 62c24b1..0094810 100644
--- a/drivers/infiniband/core/ucm.c
+++ b/drivers/infiniband/core/ucm.c
@@ -1193,6 +1193,7 @@
 	return 0;
 }
 
+static DECLARE_BITMAP(overflow_map, IB_UCM_MAX_DEVICES);
 static void ib_ucm_release_dev(struct device *dev)
 {
 	struct ib_ucm_device *ucm_dev;
@@ -1202,7 +1203,7 @@
 	if (ucm_dev->devnum < IB_UCM_MAX_DEVICES)
 		clear_bit(ucm_dev->devnum, dev_map);
 	else
-		clear_bit(ucm_dev->devnum - IB_UCM_MAX_DEVICES, dev_map);
+		clear_bit(ucm_dev->devnum - IB_UCM_MAX_DEVICES, overflow_map);
 	kfree(ucm_dev);
 }
 
@@ -1226,7 +1227,6 @@
 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
 
 static dev_t overflow_maj;
-static DECLARE_BITMAP(overflow_map, IB_UCM_MAX_DEVICES);
 static int find_overflow_devnum(void)
 {
 	int ret;