Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756022AbdLOKYM (ORCPT ); Fri, 15 Dec 2017 05:24:12 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:34914 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932149AbdLOJth (ORCPT ); Fri, 15 Dec 2017 04:49:37 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mark Bloch , Majd Dibbiny , Leon Romanovsky , Doug Ledford , Sasha Levin Subject: [PATCH 4.4 088/105] IB/mlx4: Increase maximal message size under UD QP Date: Fri, 15 Dec 2017 10:45:26 +0100 Message-Id: <20171215092310.588941135@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171215092305.994559179@linuxfoundation.org> References: <20171215092305.994559179@linuxfoundation.org> User-Agent: quilt/0.65 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 Content-Length: 1805 Lines: 49 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mark Bloch [ Upstream commit 5f22a1d87c5315a98981ecf93cd8de226cffe6ca ] Maximal message should be used as a limit to the max message payload allowed, without the headers. The ConnectX-3 check is done against this value includes the headers. When the payload is 4K this will cause the NIC to drop packets. Increase maximal message to 8K as workaround, this shouldn't change current behaviour because we continue to set the MTU to 4k. To reproduce; set MTU to 4296 on the corresponding interface, for example: ifconfig eth0 mtu 4296 (both server and client) On server: ib_send_bw -c UD -d mlx4_0 -s 4096 -n 1000000 -i1 -m 4096 On client: ib_send_bw -d mlx4_0 -c UD -s 4096 -n 1000000 -i 1 -m 4096 Fixes: 6e0d733d9215 ("IB/mlx4: Allow 4K messages for UD QPs") Signed-off-by: Mark Bloch Reviewed-by: Majd Dibbiny Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/mlx4/qp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/infiniband/hw/mlx4/qp.c +++ b/drivers/infiniband/hw/mlx4/qp.c @@ -1564,7 +1564,7 @@ static int __mlx4_ib_modify_qp(struct ib context->mtu_msgmax = (IB_MTU_4096 << 5) | ilog2(dev->dev->caps.max_gso_sz); else - context->mtu_msgmax = (IB_MTU_4096 << 5) | 12; + context->mtu_msgmax = (IB_MTU_4096 << 5) | 13; } else if (attr_mask & IB_QP_PATH_MTU) { if (attr->path_mtu < IB_MTU_256 || attr->path_mtu > IB_MTU_4096) { pr_err("path MTU (%u) is invalid\n",