From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-by2nam01on0130.outbound.protection.outlook.com ([104.47.34.130]:18358 "EHLO NAM01-BY2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932333AbeDIAdt (ORCPT ); Sun, 8 Apr 2018 20:33:49 -0400 From: Sasha Levin To: "stable@vger.kernel.org" , "linux-kernel@vger.kernel.org" CC: Logan Gunthorpe , Dave Jiang , Jon Mason , Sasha Levin Subject: [PATCH AUTOSEL for 4.9 250/293] ntb_transport: Fix bug with max_mw_size parameter Date: Mon, 9 Apr 2018 00:26:07 +0000 Message-ID: <20180409002239.163177-250-alexander.levin@microsoft.com> References: <20180409002239.163177-1-alexander.levin@microsoft.com> In-Reply-To: <20180409002239.163177-1-alexander.levin@microsoft.com> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org List-ID: From: Logan Gunthorpe [ Upstream commit cbd27448faff4843ac4b66cc71445a10623ff48d ] When using the max_mw_size parameter of ntb_transport to limit the size of the Memory windows, communication cannot be established and the queues freeze. This is because the mw_size that's reported to the peer is correctly limited but the size used locally is not. So the MW is initialized with a buffer smaller than the window but the TX side is using the full window. This means the TX side will be writing to a region of the window that points nowhere. This is easily fixed by applying the same limit to tx_size in ntb_transport_init_queue(). Fixes: e26a5843f7f5 ("NTB: Split ntb_hw_intel and ntb_transport drivers") Signed-off-by: Logan Gunthorpe Acked-by: Allen Hubbe Cc: Dave Jiang Signed-off-by: Jon Mason Signed-off-by: Sasha Levin --- drivers/ntb/ntb_transport.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c index 24222a5d8df2..da95bd8f0f72 100644 --- a/drivers/ntb/ntb_transport.c +++ b/drivers/ntb/ntb_transport.c @@ -996,6 +996,9 @@ static int ntb_transport_init_queue(struct ntb_transpor= t_ctx *nt, mw_base =3D nt->mw_vec[mw_num].phys_addr; mw_size =3D nt->mw_vec[mw_num].phys_size; =20 + if (max_mw_size && mw_size > max_mw_size) + mw_size =3D max_mw_size; + tx_size =3D (unsigned int)mw_size / num_qps_mw; qp_offset =3D tx_size * (qp_num / mw_count); =20 --=20 2.15.1