From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759814AbYBEVzV (ORCPT ); Tue, 5 Feb 2008 16:55:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757800AbYBEVzJ (ORCPT ); Tue, 5 Feb 2008 16:55:09 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:53254 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757256AbYBEVzH (ORCPT ); Tue, 5 Feb 2008 16:55:07 -0500 Date: Tue, 5 Feb 2008 22:54:54 +0100 From: Ingo Molnar To: Sam Ravnborg Cc: Linus Torvalds , Thomas Gleixner , "H. Peter Anvin" , linux-kernel@vger.kernel.org Subject: Re: [git pull] x86 updates Message-ID: <20080205215454.GA20724@elte.hu> References: <20080204161219.GA8092@elte.hu> <20080205192236.GA26426@uranus.ravnborg.org> <20080205210508.GA14708@elte.hu> <20080205211710.GA27589@uranus.ravnborg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080205211710.GA27589@uranus.ravnborg.org> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Sam Ravnborg wrote: > > btw., what's the practical consequence of getting these section > > flags wrong - for example writable data can end up in executable > > section accidentally and be marked readonly by RODATA? Or can > > anything more serious happen? (they cannot get into any of the > > discarded sections, we filter for them explicitly in the linker > > scripts) > > I have not investigated this. My attention were due to section > mismatch warnings pointing to section names I could not find in the > code. When I did an objdump of vmlinux the funny section names were > gone so I expected ld had recognized them and merged them somehow - > but I did not look closer as my focus was to get rid of them anyway. ah, indeed. if we have the same section name but different attributes then i guess gas/ld resolves the conflict by auto-generating these .1/.2, etc. artificial sections. They dont show up in the vmlinux because they went through the linker scripts that merges them into a single output section. But modpost picks up those pre-merge names. > I also did a quick skimming of info ld - but no luck. Peter pointed me to "info gas", which has a "Sections and Relocation" chapter. Ingo