From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Marchand , Doug Ledford , Sasha Levin Subject: [PATCH 4.9 050/104] IB/rxe: increment msn only when completing a request Date: Fri, 22 Dec 2017 09:46:16 +0100 Message-Id: <20171222084613.443143548@linuxfoundation.org> In-Reply-To: <20171222084609.262099650@linuxfoundation.org> References: <20171222084609.262099650@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Marchand [ Upstream commit 9fcd67d1772c43d2f23e8fca56acc7219e991676 ] According to C9-147, MSN should only be incremented when the last packet of a multi packet request has been received. "Logically, the requester associates a sequential Send Sequence Number (SSN) with each WQE posted to the send queue. The SSN bears a one- to-one relationship to the MSN returned by the responder in each re- sponse packet. Therefore, when the requester receives a response, it in- terprets the MSN as representing the SSN of the most recent request completed by the responder to determine which send WQE(s) can be completed." Fixes: 8700e3e7c485 ("Soft RoCE driver") Signed-off-by: David Marchand Signed-off-by: Doug Ledford Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/sw/rxe/rxe_resp.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) --- a/drivers/infiniband/sw/rxe/rxe_resp.c +++ b/drivers/infiniband/sw/rxe/rxe_resp.c @@ -799,18 +799,17 @@ static enum resp_states execute(struct r /* Unreachable */ WARN_ON(1); - /* We successfully processed this new request. */ - qp->resp.msn++; - /* next expected psn, read handles this separately */ qp->resp.psn = (pkt->psn + 1) & BTH_PSN_MASK; qp->resp.opcode = pkt->opcode; qp->resp.status = IB_WC_SUCCESS; - if (pkt->mask & RXE_COMP_MASK) + if (pkt->mask & RXE_COMP_MASK) { + /* We successfully processed this new request. */ + qp->resp.msn++; return RESPST_COMPLETE; - else if (qp_type(qp) == IB_QPT_RC) + } else if (qp_type(qp) == IB_QPT_RC) return RESPST_ACKNOWLEDGE; else return RESPST_CLEANUP;