Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753116AbaLEWyd (ORCPT ); Fri, 5 Dec 2014 17:54:33 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:53996 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752285AbaLEWqL (ORCPT ); Fri, 5 Dec 2014 17:46:11 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chris Moore , Or Gerlitz , Nicholas Bellinger Subject: [PATCH 3.17 033/122] ib_isert: Add max_send_sge=2 minimum for control PDU responses Date: Fri, 5 Dec 2014 14:43:27 -0800 Message-Id: <20141205223310.458327167@linuxfoundation.org> X-Mailer: git-send-email 2.1.3 In-Reply-To: <20141205223305.514276242@linuxfoundation.org> References: <20141205223305.514276242@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Or Gerlitz commit f57915cfa5b2b14c1cffa2e83c034f55e3f0e70d upstream. This patch adds a max_send_sge=2 minimum in isert_conn_setup_qp() to ensure outgoing control PDU responses with tx_desc->num_sge=2 are able to function correctly. This addresses a bug with RDMA hardware using dev_attr.max_sge=3, that in the original code with the ConnectX-2 work-around would result in isert_conn->max_sge=1 being negotiated. Originally reported by Chris with ocrdma driver. Reported-by: Chris Moore Tested-by: Chris Moore Signed-off-by: Or Gerlitz Signed-off-by: Nicholas Bellinger Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/ulp/isert/ib_isert.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/infiniband/ulp/isert/ib_isert.c +++ b/drivers/infiniband/ulp/isert/ib_isert.c @@ -115,9 +115,12 @@ isert_conn_setup_qp(struct isert_conn *i attr.cap.max_recv_wr = ISERT_QP_MAX_RECV_DTOS; /* * FIXME: Use devattr.max_sge - 2 for max_send_sge as - * work-around for RDMA_READ.. + * work-around for RDMA_READs with ConnectX-2. + * + * Also, still make sure to have at least two SGEs for + * outgoing control PDU responses. */ - attr.cap.max_send_sge = device->dev_attr.max_sge - 2; + attr.cap.max_send_sge = max(2, device->dev_attr.max_sge - 2); isert_conn->max_sge = attr.cap.max_send_sge; attr.cap.max_recv_sge = 1; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/