Messages in this thread | | | Date | Thu, 2 Aug 2007 07:13:23 +0200 | From | Borislav Petkov <> | Subject | Re: 2.6.23-rc1: no setup signature found... SOLVED! |
| |
On Wed, Aug 01, 2007 at 10:36:07AM -0400, H. Peter Anvin wrote: > Borislav Petkov wrote: >> Breakpoint 4, 0x00040200 in ?? () >> 1: x/i ($cs << 4) + $eip 0x40300: lea (%si),%dx >> (gdb) c >> Continuing. >> if i do delete here, it loads the second stage of grub and continues to >> load the >> kernel. Is there another way to land at the jmp instruction instead of >> poking >> blindly, maybe disassemble something parts of the initial code. \me >> reading >> grub-docs... > > If you do "delete" without a breakpoint number, you're deleting all > breakpoints. I just experimented with grub, and it looks like it should > break at 0x90200, so just set that breakpoint and none of the others. > > -hpa
Hi,
now this is one of those cases where one tries to shoot a small fly with a nuclear missile. The first assumption that something was wrong with the kernel setup code was wrong and here's how i know:
The problem with my version of grub not hitting the breakpoint 0x90200 made me think that something might be messed up in the grub part of the boot sequence. Thus, i did the qemu simulation again and noticed on the initial boot screen of grub it saying "Grub version 0.91." However, you remember from a different post that the version of grub i have is the latest to be found in debian unstable, 0.97-29, so i thought that something has to be wrong with it and especially with all those grub stages binaries, in my case in /boot/grub, which grub-install setups. Checking their timestamps revealed that the files are from 2004 so i thought, well, these are OLD! :) After refreshing the grub installation and replacing the stages-binaries with the fresh ones, the kernel booted just fine :), here:
[boris@gollum:07:02:07:~:9994)-> uname -a Linux gollum 2.6.22-4fd06960f120e02e9abc802a09f9511c400042a5-12 #12 PREEMPT Thu Jul 26 18:08:34 CEST 2007 i686 GNU/Linux
so i guess the problem was with the ancient parts of a grub installation i had lying around which weren't replaced by the apt-get update process and somehow messed up newer grub versions. Anyway, in the end one still learns a lot while at it.
Thanks for your help.
-- Regards/Gruß, Boris. - 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/
| |