From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757214AbaIWXiT (ORCPT ); Tue, 23 Sep 2014 19:38:19 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:39277 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754849AbaIWXiR (ORCPT ); Tue, 23 Sep 2014 19:38:17 -0400 Date: Tue, 23 Sep 2014 16:38:16 -0700 From: Andrew Morton To: Peter Foley Cc: ashutosh dixit , Randy Dunlap , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" , "Dutt, Sudeep" , "Rao, Nikhil" , Greg Kroah-Hartman Subject: Re: [PATCH linux-next] Documentation: mic: mpssd: Disable mpssd builds for kernels < 3.13 Message-Id: <20140923163816.2f3cf938c7815424e55e444f@linux-foundation.org> In-Reply-To: References: <5421EA22.6000206@infradead.org> X-Mailer: Sylpheed 3.2.0beta5 (GTK+ 2.24.10; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 23 Sep 2014 19:23:39 -0400 Peter Foley wrote: > On Tue, Sep 23, 2014 at 6:59 PM, ashutosh dixit > wrote: > > Correct, if things in Documentation will be compiled against the headers > > in the kernel source tree then this patch is not required. However, > > Andrew had reported the following compile error: > > > >> In file included from Documentation/mic/mpssd/sysfs.c:21: > >> Documentation/mic/mpssd/mpssd.h:55:30: error: linux/virtio_ids.h: No such file or directory > > > > which made it appear to us that Documentation was being compiled against > > headers installed on the system, not headers in the kernel source > > tree. The patch was submitted to address this latter case, but if that > > does not occur it is not required. > > > Alright, if you want to handle the case where somebody is trying to > build against old and incompatible headers, > just have a #error "Your kernel headers are too old, at least 3.13 is > required" at the top of mpssd.c instead of having it fail at runtime. > This build error is caused by compiling mpssd prior to `make headers_install'. There's really no reason to check the kernel version. If someone transplants mpssd out of its distributed kernel and into some older kernel then a miscompile is their problem - their backport is incomplete.