From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f178.google.com (mail-pd0-f178.google.com [209.85.192.178]) by dpdk.org (Postfix) with ESMTP id 68E90C404 for ; Fri, 10 Jul 2015 19:29:06 +0200 (CEST) Received: by pdjr16 with SMTP id r16so26295154pdj.3 for ; Fri, 10 Jul 2015 10:29:05 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-type:content-transfer-encoding; bh=rR5OHg08krzEa2xU2DLK06Nsud/QU7qwqN1gPDlacYs=; b=CUPMGh/tI+sGEGP7gZaWfMwfHJKmgQRR+RGj6yiYiZDGvHDa8Pys7qw5N/YPWcT8xp Mfn+WjO4l6vBkAUa2OXN1LL8FTyBRMKJeXL2PyDm58yg0Kwx830xFx+6MZOAu0uu9A47 vTqsN08FoZLu1M0d2tOkMQYIAdhCVqY7JAvt0yP8dvV/kXzaWi6XMu3LpIQHmDxW5Y/6 /QRyjqGQStESNYa5UNWYTtDcJyNB5ycc2PMtM+3MxOeSrbcM6FWjy3jhmgbTwchfJDNI i5V//qfS5+AFBiDP1rDY6Nz5tTIPYz5wCqGAe1XQSBYFCbEMsGbFToYZqBgWJfyfyZfr DFxg== X-Gm-Message-State: ALoCoQkw7CPW+WSRJsDJM6+ZgGYNi0gpXabnKtcCxbKSwukMu69mWp5OuQlITfjiCqgjijFEK8fY X-Received: by 10.70.131.35 with SMTP id oj3mr44015337pdb.80.1436549345816; Fri, 10 Jul 2015 10:29:05 -0700 (PDT) Received: from urahara (static-50-53-82-155.bvtn.or.frontiernet.net. [50.53.82.155]) by smtp.gmail.com with ESMTPSA id pn6sm10204245pdb.72.2015.07.10.10.29.04 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 10 Jul 2015 10:29:05 -0700 (PDT) Date: Fri, 10 Jul 2015 10:29:14 -0700 From: Stephen Hemminger To: Thomas Monjalon Message-ID: <20150710102914.3db19e8a@urahara> In-Reply-To: <2141795.rDVNFltQvv@xps13> References: <1436484387-29273-1-git-send-email-stephen@networkplumber.org> <1436484387-29273-2-git-send-email-stephen@networkplumber.org> <2141795.rDVNFltQvv@xps13> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: dev@dpdk.org, Stephen Hemminger Subject: Re: [dpdk-dev] [PATCH v2 1/2] vfio: fix build if build envrionment is on old kernel X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 10 Jul 2015 17:29:06 -0000 On Fri, 10 Jul 2015 01:43:17 +0200 Thomas Monjalon wrote: > 2015-07-09 16:26, Stephen Hemminger: > > From: Stephen Hemminger > > > > The build of DPDK may be done on a system where Linux headers > > in /usr/include (and therefore kernel version macro) are much > > older than the target runtime system. > > It seems strange wanting to build a feature not present in the kernel > headers. Why not upgrading the build system kernel? The build machine is running Debian with stock headers and kernel. I can see many people having build environments controlled by other parts of organization where you are not allowed to update packages. > > In order to work around this, one solution is to put in simplified > > kernel header (this is what the compat stuff is already doing). > > The other solution (as already suggested by Anatoly) is to have a configure > script (not an autotool one). It would make clear that VFIO support is not > built. > Ref: http://dpdk.org/ml/archives/dev/2015-April/016772.html That won't solve the issue. The other possiblities are: 1. Fail the build if VFIO is configured but headers files are missing. This is better than surprising user at runtime. 2. Don't use /usr/include/linux as path as expected path of kernel headers instead use build path (this is what modules do).