From: Vitaly Fertman <vitaly.fertman@oracle.com>
Date: Tue, 7 Dec 2010 22:00:13 +0000 (+0300)
Subject: b=21804 protect rpc by refcount in ptlrpc_server_handle_req_in()
X-Git-Tag: 2.0.59.0~39
X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=commitdiff_plain;h=9afee0366ab03c9feba88cc8eb0027aa0fb9bf6b;ds=sidebyside

b=21804 protect rpc by refcount in ptlrpc_server_handle_req_in()

i=johann
i=adilger

ptlrpc_hpreq_init() inserts rpc to the export list and by the time
of ptlrpc_server_request_add() it could be already handled and
released. To not lose request in between, take an extra reference
on the request.
---

diff --git a/lustre/ptlrpc/service.c b/lustre/ptlrpc/service.c
index 3b9faab..cfb798f 100644
--- a/lustre/ptlrpc/service.c
+++ b/lustre/ptlrpc/service.c
@@ -1477,6 +1477,11 @@ ptlrpc_server_handle_req_in(struct ptlrpc_service *svc)
         svc->srv_n_queued_reqs--;
         /* Consider this still a "queued" request as far as stats are
            concerned */
+        /* ptlrpc_hpreq_init() inserts it to the export list and by the time
+         * of ptlrpc_server_request_add() it could be already handled and
+         * released. To not lose request in between, take an extra reference
+         * on the request. */
+        ptlrpc_request_addref(req);
         cfs_spin_unlock(&svc->srv_lock);
 
         /* go through security check/transform */
@@ -1586,9 +1591,11 @@ ptlrpc_server_handle_req_in(struct ptlrpc_service *svc)
         if (rc)
                 GOTO(err_req, rc);
         cfs_waitq_signal(&svc->srv_waitq);
+        ptlrpc_server_drop_request(req);
         RETURN(1);
 
 err_req:
+        ptlrpc_server_drop_request(req);
         cfs_spin_lock(&svc->srv_rq_lock);
         svc->srv_n_active_reqs++;
         cfs_spin_unlock(&svc->srv_rq_lock);