Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161798AbWHJNNv (ORCPT ); Thu, 10 Aug 2006 09:13:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161796AbWHJNNu (ORCPT ); Thu, 10 Aug 2006 09:13:50 -0400 Received: from e1.ny.us.ibm.com ([32.97.182.141]:6060 "EHLO e1.ny.us.ibm.com") by vger.kernel.org with ESMTP id S1161798AbWHJNNt (ORCPT ); Thu, 10 Aug 2006 09:13:49 -0400 Date: Thu, 10 Aug 2006 09:13:23 -0400 From: Vivek Goyal To: "Eric W. Biederman" Cc: Don Zickus , fastboot@osdl.org, Horms , Jan Kratochvil , "H. Peter Anvin" , Magnus Damm , linux-kernel@vger.kernel.org Subject: Re: [Fastboot] [CFT] ELF Relocatable x86 and x86_64 bzImages Message-ID: <20060810131323.GB9888@in.ibm.com> Reply-To: vgoyal@in.ibm.com References: <20060804210826.GE16231@redhat.com> <20060804234327.GF16231@redhat.com> <20060807174439.GJ16231@redhat.com> <20060807235727.GM16231@redhat.com> <20060809200642.GD7861@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2226 Lines: 53 On Thu, Aug 10, 2006 at 12:09:56AM -0600, Eric W. Biederman wrote: > Don Zickus writes: > > >> Looking at my build it appears bytes_out is being placed in the .bss. > >> A little odd since it is zero initialized but no big deal. > >> Could you confirm that bytes_out is being placed in the .bss section > >> by inspecting arch/x86_64/boot/compresssed/misc.o and > >> arch/x86_64/boot_compressed/vmlinux. "readelf -a $file" and then > >> looking up the section number and looking at the section table to see > >> which section it is was my technique. > >> > >> If bytes_out is in the .bss for you then I suspect something is not > >> correctly zeroing the .bss. Or else the .bss is being stomped. > >> > >> I'm not certain how rep stosb can be done wrong but some bad pointer > >> math could have done it. > >> > >> Eric > > > > It seems Vivek came up with a solution that works. He sent it to me this > > morning. We tested a bunch of machines and things seem to work now. It > > looks like it mimics the i386 behaviour now. > > Yes, this looks right. It looks like I forgot to make this change when > the logic from i386 was adopted to x86_64, ages ago. > > This is exactly the place in the code I would have expected a bug > from the symptoms you were seeing. > > Thanks all I will include this in my version of the patches. Apart from this I think something is still off on x86_64. I have not been able to make kdump work on x86_64. Second kernel simply hangs. Two different machines are showing different results. - On one machine, it seems to be stuck somewhere in decompress_kernel(). Serial console is not behaving properly even with earlyprintk(). Somehow I feel it is some bss corruption even after my changes. - Other machines seems to be going till start_kernel() and even after that (No messages on the console, all serial debugging) and then either it hangs or jumps back to BIOS. Will look more into it. Thanks Vivek - 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/