From: Chuck Lever <chuck.lever@xxxxxxxxxx> I still see "RPC: Could not send backchannel reply error: -110" quite often, along with slow-running tests. Debugging shows that the backchannel is still stumbling when it has to queue a callback reply on a busy transport. Note that every one of these timeouts causes a connection loss by virtue of the xprt_conditional_disconnect() call in that arm of call_cb_transmit_status(). I found that setting to_maxval is necessary to get the RPC timeout logic to behave whenever to_exponential is not set. Fixes: 57331a59ac0d ("NFSv4.1: Use the nfs_client's rpc timeouts for backchannel") Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> --- net/sunrpc/svc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 965a27806bfd..f4ddb2961042 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -1643,6 +1643,7 @@ void svc_process_bc(struct rpc_rqst *req, struct svc_rqst *rqstp) timeout.to_initval = req->rq_xprt->timeout->to_initval; timeout.to_retries = req->rq_xprt->timeout->to_retries; } + timeout.to_maxval = timeout.to_initval; memcpy(&req->rq_snd_buf, &rqstp->rq_res, sizeof(req->rq_snd_buf)); task = rpc_run_bc_task(req, &timeout); -- 2.45.1