From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 419DF5398 for ; Tue, 11 Jul 2017 03:56:19 +0200 (CEST) Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Jul 2017 18:56:18 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.40,343,1496127600"; d="scan'208";a="123504432" Received: from fmsmsx108.amr.corp.intel.com ([10.18.124.206]) by orsmga005.jf.intel.com with ESMTP; 10 Jul 2017 18:56:17 -0700 Received: from fmsmsx153.amr.corp.intel.com (10.18.125.6) by FMSMSX108.amr.corp.intel.com (10.18.124.206) with Microsoft SMTP Server (TLS) id 14.3.319.2; Mon, 10 Jul 2017 18:56:17 -0700 Received: from shsmsx101.ccr.corp.intel.com (10.239.4.153) by FMSMSX153.amr.corp.intel.com (10.18.125.6) with Microsoft SMTP Server (TLS) id 14.3.319.2; Mon, 10 Jul 2017 18:56:17 -0700 Received: from shsmsx103.ccr.corp.intel.com ([169.254.4.116]) by SHSMSX101.ccr.corp.intel.com ([169.254.1.197]) with mapi id 14.03.0319.002; Tue, 11 Jul 2017 09:56:15 +0800 From: "Tan, Jianfeng" To: Stephen Hemminger , "dev@dpdk.org" Thread-Topic: [dpdk-dev] [RFC] pci: force address of mappings in secondary process Thread-Index: AQHS+eLgyG6dcA8FKUmPJC0hVH7QXaJN3UYw Date: Tue, 11 Jul 2017 01:56:15 +0000 Message-ID: References: <20170711011242.4606-1-stephen@networkplumber.org> In-Reply-To: <20170711011242.4606-1-stephen@networkplumber.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [RFC] pci: force address of mappings in secondary process X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 11 Jul 2017 01:56:19 -0000 > -----Original Message----- > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Stephen > Hemminger > Sent: Tuesday, July 11, 2017 9:13 AM > To: dev@dpdk.org > Cc: Stephen Hemminger > Subject: [dpdk-dev] [RFC] pci: force address of mappings in secondary > process >=20 > The PCI memory resources in the secondary process should be in > the exact same location as the primary process. Otherwise > there is a risk of a stray pointer. >=20 > Not sure if this is right, but it looks like a potential > problem. >=20 > --- > lib/librte_eal/common/eal_common_pci_uio.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) >=20 > diff --git a/lib/librte_eal/common/eal_common_pci_uio.c > b/lib/librte_eal/common/eal_common_pci_uio.c > index 367a6816dcb8..2156b1a436c4 100644 > --- a/lib/librte_eal/common/eal_common_pci_uio.c > +++ b/lib/librte_eal/common/eal_common_pci_uio.c > @@ -77,7 +77,7 @@ pci_uio_map_secondary(struct rte_pci_device *dev) >=20 > void *mapaddr =3D pci_map_resource(uio_res- > >maps[i].addr, > fd, (off_t)uio_res->maps[i].offset, > - (size_t)uio_res->maps[i].size, 0); > + (size_t)uio_res->maps[i].size, > MAP_FIXED); > /* fd is not needed in slave process, close it */ > close(fd); > if (mapaddr !=3D uio_res->maps[i].addr) { > -- > 2.11.0 +1 for this RFC. I also once encounter such problem, and I use the same way= to solve it. The addr parameter of mmap() syscall is only a hint instead o= f a must even the VMA is not occupied yet. Thanks, Jianfeng