[PATCH v6 6/7] nfsd: handle NFS4ERR_BADSLOT on CB_SEQUENCE better

[Jeff Layton]

Currently it just restarts the call, without getting a new slot.

Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
 fs/nfsd/nfs4callback.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 18803ebe2bddd433308cabd6f99b64ec887069a7..8ba1a2831e8601ac3af9c5f147d3dcddcc1bec77 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -1389,6 +1389,13 @@ static bool nfsd4_cb_sequence_done(struct rpc_task *task, struct nfsd4_callback
 		rpc_delay(task, 2 * HZ);
 		return false;
 	case -NFS4ERR_BADSLOT:
+		/*
+		 * BADSLOT means that the client and server are out of sync
+		 * as to the backchannel parameters. Mark the backchannel faulty
+		 * and restart the RPC, but leak the slot so no one uses it.
+		 */
+		nfsd4_mark_cb_fault(cb->cb_clp);
+		cb->cb_held_slot = -1;
 		goto retry_nowait;
 	case -NFS4ERR_SEQ_MISORDERED:
 		if (session->se_cb_seq_nr[cb->cb_held_slot] != 1) {

-- 
2.48.1