nvmet-fcloop: call done callback even when remote port is gone

JIRA: https://issues.redhat.com/browse/RHEL-114502

When the target port is gone, it's not possible to access any of the
request resources. The function should just silently drop the response.
The comment is misleading in this regard.

Though it's still necessary to call the driver via the ->done callback
so the driver is able to release all resources.

Reported-by: Yi Zhang <yi.zhang@redhat.com>
Closes: https://lore.kernel.org/all/CAHj4cs-OBA0WMt5f7R0dz+rR4HcEz19YLhnyGsj-MRV3jWDsPg@mail.gmail.com/
Fixes: 84eedce ("nvmet-fcloop: drop response if targetport is gone")
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Daniel Wagner <wagi@kernel.org>
Signed-off-by: Keith Busch <kbusch@kernel.org>
(cherry picked from commit 10c165a)
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>

Author: maurizio-lombardi

drivers/nvme/target/fcloop.c

@@ -496,13 +496,15 @@ fcloop_t2h_xmt_ls_rsp(struct nvme_fc_local_port *localport,
 	if (!targetport) {
 		/*
 		 * The target port is gone. The target doesn't expect any
-		 * response anymore and the ->done call is not valid
-		 * because the resources have been freed by
-		 * nvmet_fc_free_pending_reqs.
+		 * response anymore and thus lsreq can't be accessed anymore.
 		 *
 		 * We end up here from delete association exchange:
 		 * nvmet_fc_xmt_disconnect_assoc sends an async request.
+		 *
+		 * Return success because this is what LLDDs do; silently
+		 * drop the response.
 		 */
+		lsrsp->done(lsrsp);
 		kmem_cache_free(lsreq_cache, tls_req);
 		return 0;
 	}