From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail2.matrix-vision.com ([85.214.244.251]) by linuxtogo.org with esmtp (Exim 4.72) (envelope-from ) id 1Q7otm-000591-VA; Thu, 07 Apr 2011 15:05:23 +0200 Received: from mail2.matrix-vision.com (localhost [127.0.0.1]) by mail2.matrix-vision.com (Postfix) with ESMTP id BC41F3F63B; Thu, 7 Apr 2011 15:03:14 +0200 (CEST) Received: from erinome (g2.matrix-vision.com [80.152.136.245]) by mail2.matrix-vision.com (Postfix) with ESMTPA id 6DABB3F623; Thu, 7 Apr 2011 15:03:14 +0200 (CEST) Received: from erinome (localhost [127.0.0.1]) by erinome (Postfix) with ESMTP id 0025C6F8A; Thu, 7 Apr 2011 15:03:14 +0200 (CEST) Received: by erinome (Postfix, from userid 108) id E99116F9C; Thu, 7 Apr 2011 15:03:13 +0200 (CEST) Received: from [192.168.65.46] (host65-46.intern.matrix-vision.de [192.168.65.46]) by erinome (Postfix) with ESMTPA id D7C336F8A; Thu, 7 Apr 2011 15:03:13 +0200 (CEST) Message-ID: <4D9DB612.80002@matrix-vision.de> Date: Thu, 07 Apr 2011 15:03:14 +0200 From: Michael Jones User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.12) Gecko/20101029 Lightning/1.0b2 Thunderbird/3.1.6 MIME-Version: 1.0 To: openembedded-devel@lists.openembedded.org References: <4D832AA4.1020701@matrix-vision.de> <1301060302.3018.129.camel@rex> <4D8CA329.10407@matrix-vision.de> <1301064949.3018.147.camel@rex> <4D8CBCA4.2070603@matrix-vision.de> <1301316136.3018.189.camel@rex> In-Reply-To: X-MV-Disclaimer: true (erinome) X-AV-Checked: ClamAV using ClamSMTP (erinome) X-AV-Checked: ClamAV using ClamSMTP (mail2) Cc: koen@dominion.thruhere.net, openembedded-core@lists.openembedded.org Subject: Re: [oe] staging & using kernel headers X-BeenThere: openembedded-core@lists.openembedded.org X-Mailman-Version: 2.1.11 Precedence: list Reply-To: Patches and discussions about the oe-core layer List-Id: Patches and discussions about the oe-core layer List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 07 Apr 2011 13:05:23 -0000 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 03/28/2011 06:39 PM, Khem Raj wrote: > On Mon, Mar 28, 2011 at 5:42 AM, Richard Purdie > wrote: >> >>> OK, so here's what I'm realizing, please correct me if I'm wrong: >>> What I did unconventionally (ie. wrong) was to use a kernel version >>> newer than my linux-libc-headers were. I should create a new >>> linux-libc-headers recipe, as I had done with the kernel recipe, and >>> build glibc and linux-libc-headers using my 2.6.38 kernel. >> >> We should *always* be using linux-libc-headers >= to the kernel version >> being used. >> > > If you use newer kernel should work ok why is that a problem ? kernel > syscalls are backward compatible > and we use oldest kernel version of like 2.6.16 for eglibc to build > against so it should not be a problem > to use different versions for kernel and kernel-headers. I think your > problem lies elsewhere > There is a kernel interface in the V4L2 development tree that is being introduced in 2.6.39 (but which in my local branch is patched on top of 2.6.38). The problem I kicked off this thread with was due to ti-dmai and gstreamer-ti _directly_ using the headers from this kernel, which since 2.6.32 gives a warning for doing so. Of course, I'm using the newer kernel for a reason, which is to use the new kernel API. So I need to use the headers from my local development kernel (built by an OE recipe) when building that application, which I'm now writing the recipe for. I thought at first that userspace apps were automatically built against the headers derived from the kernel being used (which is what the ti recipes do, but incorrectly). During this thread I realized that linux-libc-headers is a separate recipe intended for supplying user headers. I suppose I will use the method for my V4L2 app that I kicked off this thread with- staging the development kernel's headers with make_install somewhere which can be used by my app. As Richard pointed out earlier in this thread, making the package dependent on the kernel makes the package machine dependent. This is OK for this package, but I still want all other apps to be Angstrom-generic apps, so I don't want to change linux-libc-headers to use my kernel headers after all. MATRIX VISION GmbH, Talstrasse 16, DE-71570 Oppenweiler Registergericht: Amtsgericht Stuttgart, HRB 271090 Geschaeftsfuehrer: Gerhard Thullner, Werner Armingeon, Uwe Furtner