Re: PATCH: Fix removed sections (Re: 2.12.90.0.12 Kernel Miscompile)

["Leonard N. Zubkoff" <lnz at dandelion dot com>]

  Date: Wed, 3 Jul 2002 09:12:37 -0700
  From: "H. J. Lu" <hjl@lucon.org>

  Could you please try

  # objdump --full vmlinux.12 > 12
  # objdump --full vmlinux.14 > 14

  to see which sections differ.


  H.J.

The interesting difference is in the .text section:

4786c4786
<  c0112ad0 0083c410 83c40cc3 5653b900 000000bb  ........VS......
---
>  c0112ad0 0083c410 83c40cc3 5653b9e0 7926c0bb  ........VS..y&..

There are two other differecnes, but they are simply the date and time of the
compilation.

Looking at System.map, we find:

c0112ab4 T iounmap
c0112ad8 T search_exception_table

Looking at linux/arch/i386/mm/extable.c, I see that my compilation might not
match yours, since I have CONFIG_MODULES turned off in my .config.

Using GDB to disassemble search_exception_table in these two kernels, we have:

midkemia:/ss/linux/kelewan> gdb linux/vmlinux.12
...
0xc0112ad8 <search_exception_table>:	push   %esi
0xc0112ad9 <search_exception_table+1>:	push   %ebx
0xc0112ada <search_exception_table+2>:	mov    $0x0,%ecx
0xc0112adf <search_exception_table+7>:	mov    $0xc0268ad0,%ebx
0xc0112ae4 <search_exception_table+12>:	mov    0xc(%esp,1),%esi
0xc0112ae8 <search_exception_table+16>:	cmp    %ebx,%ecx

midkemia:/ss/linux/kelewan> gdb linux/vmlinux.14
...
0xc0112ad8 <search_exception_table>:	push   %esi
0xc0112ad9 <search_exception_table+1>:	push   %ebx
0xc0112ada <search_exception_table+2>:	mov    $0xc02679e0,%ecx
0xc0112adf <search_exception_table+7>:	mov    $0xc0268ad0,%ebx
0xc0112ae4 <search_exception_table+12>:	mov    0xc(%esp,1),%esi
0xc0112ae8 <search_exception_table+16>:	cmp    %ebx,%ecx

>From looking at the source code, I suspect that the problem lies with resolving
__start___ex_table or __stop___ex_table-1.

		Leonard