Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753101Ab1BVHCn (ORCPT ); Tue, 22 Feb 2011 02:02:43 -0500 Received: from smtp-outbound-2.vmware.com ([65.115.85.73]:62199 "EHLO smtp-outbound-2.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751390Ab1BVHCk (ORCPT ); Tue, 22 Feb 2011 02:02:40 -0500 Date: Mon, 21 Feb 2011 23:02:40 -0800 From: Dmitry Torokhov To: Linus Torvalds Cc: Benjamin Herrenschmidt , Rusty Russell , David Miller , linux-kernel@vger.kernel.org, geert@linux-m68k.org, linux-m68k@vger.kernel.org, linux-arch@vger.kernel.org, Mikael Starvik , Jesper Nilsson Subject: Re: [PATCH 1/3] module: deal with alignment issues in built-in module versions Message-ID: <20110222070240.GA21765@dtor-ws.eng.vmware.com> References: <20110217.140119.39175251.davem@davemloft.net> <20110217221957.GA11244@dtor-ws.eng.vmware.com> <20110217.142320.102554706.davem@davemloft.net> <1298074455.2460.85.camel@pasglop> <87pqqmrq9q.fsf@rustcorp.com.au> <1298339909.8833.135.camel@pasglop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2571 Lines: 71 On Mon, Feb 21, 2011 at 06:03:16PM -0800, Linus Torvalds wrote: > On Mon, Feb 21, 2011 at 5:58 PM, Benjamin Herrenschmidt > wrote: > > > > The only sane thing I can see is make sure that such structures that > > we put into sections "arrays" like that are naturally aligned with > > padding. > > The sad part is, that assuming I read the gcc sources correctly (see > the earlier emails where David pointed to it), that alignment is: > - architecture-specific > - depends on the size of the structure > - seems to depend on the version of gcc itself. > > The _one_ safe case is likely to be "structure size is a power of > two". And it does look like using a pointer is going to be safe, not > only because the gcc auto-alignment only triggers for things like > structs/unions/arrays, but because at least the x86 code only does it > if the structure was bigger than the alignment size itself. > > So using pointer indirection is likely to be safe. It's still ugly and > annoying as heck, though. > Regardless the approach we'll take I think the following patch is also needed (for cris architecture). I am not sure why __param section is inly defined for one specific subarch but I they need __param they'll need __modev as well. Thanks, Dmitry >From a567280f900c15891a55e7ea4e2919b38e1d1a01 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Thu, 17 Feb 2011 13:12:26 -0800 Subject: [PATCH] cris: add missing __modver section Commit e94965ed5beb23c6fabf7ed31f625e66d7ff28de added a new __modver section to store module version information for drivers built into the kernel, but missed the fact that cris does some additional steps to set up sections. Signed-off-by: Dmitry Torokhov --- arch/cris/kernel/vmlinux.lds.S | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/arch/cris/kernel/vmlinux.lds.S b/arch/cris/kernel/vmlinux.lds.S index 4422189..fae1b7b 100644 --- a/arch/cris/kernel/vmlinux.lds.S +++ b/arch/cris/kernel/vmlinux.lds.S @@ -73,6 +73,10 @@ SECTIONS .init.data : { INIT_DATA } .init.setup : { INIT_SETUP(16) } #ifdef CONFIG_ETRAX_ARCH_V32 + __start___modver = .; + __modver : { *(__modver) } + __stop___modver = .; + __start___param = .; __param : { *(__param) } __stop___param = .; -- 1.7.3.2 -- 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/