Merge branch 'uverbs_dev_cleanups' into rdma.git for-next

For dependencies, branch based on rdma.git 'for-rc' of
https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git/

Pull 'uverbs_dev_cleanups' from Leon Romanovsky:

====================
Reuse the char device code interfaces to simplify ib_uverbs_device
creation and destruction. As part of this series, we are sending fix to
cleanup path, which was discovered during internal review,

The fix definitely can go to -rc, but it means that this series will be
dependent on rdma-rc.
====================

* branch 'uverbs_dev_cleanups':
  RDMA/uverbs: Use device.groups to initialize device attributes
  RDMA/uverbs: Use cdev_device_add() instead of cdev_add()
  RDMA/core: Depend on device_add() to add device attributes
  RDMA/uverbs: Fix error cleanup path of ib_uverbs_add_one()

Resolved conflict in ib_device_unregister_sysfs()

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 1b9951d2067e..d668682f91df 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -316,6 +316,14 @@ static bool nvme_dbbuf_update_and_check_event(u16 value, u32 *dbbuf_db,
                 old_value = *dbbuf_db;
                 *dbbuf_db = value;
 
+                /*
+                 * Ensure that the doorbell is updated before reading the event
+                 * index from memory.  The controller needs to provide similar
+                 * ordering to ensure the envent index is updated before reading
+                 * the doorbell.
+                 */
+                mb();
+
                 if (!nvme_dbbuf_need_event(*dbbuf_ei, value, old_value))
                         return false;
         }