NFSD: fix hang in nfsd4_shutdown_callback

commit 036ac2778f7b28885814c6fbc07e156ad1624d03 upstream.

If nfs4_client is in courtesy state then there is no point to send
the callback. This causes nfsd4_shutdown_callback to hang since
cl_cb_inflight is not 0. This hang lasts about 15 minutes until TCP
notifies NFSD that the connection was dropped.

This patch modifies nfsd4_run_cb_work to skip the RPC call if
nfs4_client is in courtesy state.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Fixes: 66af25799940 ("NFSD: add courteous server support for thread with only delegation")
Cc: stable@vger.kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 1cdfff9de6e28a4cbf71e36148e0401d70a45fcc..272d3facfff9d34ee1896c6a41136c7ea566f36a 100644 (file)
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -1410,8 +1410,11 @@ nfsd4_run_cb_work(struct work_struct *work)
                nfsd4_process_cb_update(cb);
 
        clnt = clp->cl_cb_client;
-       if (!clnt) {
-               /* Callback channel broken, or client killed; give up: */
+       if (!clnt || clp->cl_state == NFSD4_COURTESY) {
+               /*
+                * Callback channel broken, client killed or
+                * nfs4_client in courtesy state; give up.
+                */
                nfsd41_destroy_cb(cb);
                return;
        }