Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755519AbbDNPLV (ORCPT ); Tue, 14 Apr 2015 11:11:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54730 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753812AbbDNPLM (ORCPT ); Tue, 14 Apr 2015 11:11:12 -0400 Date: Tue, 14 Apr 2015 10:11:10 -0500 From: Josh Poimboeuf To: Minfei Huang Cc: sjenning@redhat.com, jkosina@suse.cz, vojtech@suse.cz, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] livepatch: Fix the bug if the function name is larger than KSYM_NAME_LEN-1 Message-ID: <20150414151110.GL4412@treble.hsd1.ky.comcast.net> References: <1428844554-4015-1-git-send-email-minfei.huang@hotmail.com> <20150413231305.GD4412@treble.hsd1.ky.comcast.net> <20150414045739.GG4412@treble.hsd1.ky.comcast.net> <20150414051113.GH4412@treble.hsd1.ky.comcast.net> <20150414053247.GI4412@treble.hsd1.ky.comcast.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1258 Lines: 31 On Tue, Apr 14, 2015 at 01:45:49PM +0800, Minfei Huang wrote: > On 04/14/15 at 12:32P, Josh Poimboeuf wrote: > > On Tue, Apr 14, 2015 at 01:29:50PM +0800, Minfei Huang wrote: > > > > > > For end user, they may know litter about restriction of kallsyms and > > > livepatch. How can they know the restriction that function name is > > > limited to 127? > > > > As I mentioned above, I think kallsyms.c should fail the build if it > > encounters a symbol longer than KSYM_NAME_LEN. > > > > I dont think it is a good idea to handle this case like that. The > function name is only for human recognization. Why the compiler fails > to build it? Well, the function name isn't only for human recognition. kpatch-build generates patch modules automatically. It assumes that the compiled function name matches the kallsyms name. And I'd guess that a lot of other code (both in-kernel and user space tools) make the same assumption. Not to mention that most humans would also make the same assumption... -- Josh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/