Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull rdma fixes from Jason Gunthorpe:
 "Still not much going on, the usual set of oops and driver fixes this
  time:

   - Fix two uapi breakage regressions in mlx5 drivers

   - Various oops fixes in hfi1, mlx4, umem, uverbs, and ipoib

   - A protocol bug fix for hfi1 preventing it from implementing the
     verbs API properly, and a compatability fix for EXEC STACK user
     programs

   - Fix missed refcounting in the 'advise_mr' patches merged this
     cycle.

   - Fix wrong use of the uABI in the hns SRQ patches merged this cycle"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  IB/uverbs: Fix OOPs in uverbs_user_mmap_disassociate
  IB/ipoib: Fix for use-after-free in ipoib_cm_tx_start
  IB/uverbs: Fix ioctl query port to consider device disassociation
  RDMA/mlx5: Fix flow creation on representors
  IB/uverbs: Fix OOPs upon device disassociation
  RDMA/umem: Add missing initialization of owning_mm
  RDMA/hns: Update the kernel header file of hns
  IB/mlx5: Fix how advise_mr() launches async work
  RDMA/device: Expose ib_device_try_get(()
  IB/hfi1: Add limit test for RC/UC send via loopback
  IB/hfi1: Remove overly conservative VM_EXEC flag check
  IB/{hfi1, qib}: Fix WC.byte_len calculation for UD_SEND_WITH_IMM
  IB/mlx4: Fix using wrong function to destroy sqp AHs under SRIOV
  RDMA/mlx5: Fix check for supported user flags when creating a QP

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index 8872453e26c0..238ec42778ef 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -156,19 +156,26 @@ struct ib_device *ib_device_get_by_index(u32 index)
 	down_read(&lists_rwsem);
 	device = __ib_device_get_by_index(index);
 	if (device) {
-		/* Do not return a device if unregistration has started. */
-		if (!refcount_inc_not_zero(&device->refcount))
+		if (!ib_device_try_get(device))
 			device = NULL;
 	}
 	up_read(&lists_rwsem);
 	return device;
 }
 
+/**
+ * ib_device_put - Release IB device reference
+ * @device: device whose reference to be released
+ *
+ * ib_device_put() releases reference to the IB device to allow it to be
+ * unregistered and eventually free.
+ */
 void ib_device_put(struct ib_device *device)
 {
 	if (refcount_dec_and_test(&device->refcount))
 		complete(&device->unreg_completion);
 }
+EXPORT_SYMBOL(ib_device_put);
 
 static struct ib_device *__ib_device_get_by_name(const char *name)
 {
@@ -303,7 +310,6 @@ struct ib_device *ib_alloc_device(size_t size)
 	rwlock_init(&device->client_data_lock);
 	INIT_LIST_HEAD(&device->client_data_list);
 	INIT_LIST_HEAD(&device->port_list);
-	refcount_set(&device->refcount, 1);
 	init_completion(&device->unreg_completion);
 
 	return device;
@@ -620,6 +626,7 @@ int ib_register_device(struct ib_device *device, const char *name,
 		goto cg_cleanup;
 	}
 
+	refcount_set(&device->refcount, 1);
 	device->reg_state = IB_DEV_REGISTERED;
 
 	list_for_each_entry(client, &client_list, list)