From: Max Gurtovoy <maxg@mellanox.com>
Date: Tue, 29 Oct 2019 16:42:27 +0200
Subject: nvme-rdma: fix a segmentation fault during module unload
Git-commit: 9ad9e8d6ca29c1446d81c6518ae634a2141dfd22
Patch-mainline: 5.4-rc7
References: bnc#1151927 5.3.15

In case there are controllers that are not associated with any RDMA
device (e.g. during unsuccessful reconnection) and the user will unload
the module, these controllers will not be freed and will access already
freed memory. The same logic appears in other fabric drivers as well.

Fixes: 87fd125344d6 ("nvme-rdma: remove redundant reference between ib_device and tagset")
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/nvme/host/rdma.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -2125,8 +2125,16 @@ err_unreg_client:
 
 static void __exit nvme_rdma_cleanup_module(void)
 {
+	struct nvme_rdma_ctrl *ctrl;
+
 	nvmf_unregister_transport(&nvme_rdma_transport);
 	ib_unregister_client(&nvme_rdma_ib_client);
+
+	mutex_lock(&nvme_rdma_ctrl_mutex);
+	list_for_each_entry(ctrl, &nvme_rdma_ctrl_list, list)
+		nvme_delete_ctrl(&ctrl->ctrl);
+	mutex_unlock(&nvme_rdma_ctrl_mutex);
+	flush_workqueue(nvme_delete_wq);
 }
 
 module_init(nvme_rdma_init_module);