From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pjotr Prins Subject: Re: why is linux-libre-headers behind linux-libre? Date: Mon, 6 Nov 2017 09:51:34 +0100 Message-ID: <20171106085134.GA24651@thebird.nl> References: <87bmkn7awd.fsf@albion.it.manchester.ac.uk> <20171031193852.GB987@macbook41> <87fu9x2df8.fsf@albion.it.manchester.ac.uk> <878tfksp03.fsf@gnu.org> <87po8vhk3q.fsf@netris.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:57841) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eBdAC-0004CT-I7 for guix-devel@gnu.org; Mon, 06 Nov 2017 03:53:49 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eBdAB-00035B-P2 for guix-devel@gnu.org; Mon, 06 Nov 2017 03:53:48 -0500 Content-Disposition: inline In-Reply-To: <87po8vhk3q.fsf@netris.org> List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: "Guix-devel" To: Mark H Weaver Cc: guix-devel , Dave Love On Mon, Nov 06, 2017 at 03:44:41AM -0500, Mark H Weaver wrote: > Are you sure about this? My impression was that binaries compiled with > newer linux-libre-headers can be run on older kernels. If you were > correct, then the binaries we've been building throughout 2017 could be > reliably run only on linux-libre-4.4 or newer. > > In fact, we've been successfully running these Guix binaries on > hydra.gnu.org with its old 2.6.x kernel, and on build slaves running > kernels older than 4.4. Furthermore, I strongly suspect that many of > our users (e.g. Trisquel users) have been running Guix on older kernels > as well, and yet I don't recall seeing any bug reports related to this. > > My recommendation would be to update linux-libre-headers to the latest > LTS kernel (currently 4.9.x) in every core-updates cycle. > > What do you think? The Linux kernel API is remarkably stable. It is indeed the reason we *can* run GNU Guix on older kernels in the first place - the kernel is our single dependency. The headers do change, but mostly due to kernel internals which are not used from glibc etc. I remember for Nix there was a breaking kernel API change at some point. But it is extremely rare. Must have been 10 years ago. Pj. --