Re: 2.5.59 vmlinux.lds.S change broke modules

[Brian Gerst]

Mikael Pettersson wrote:
> Previously today I wrote:
>  > 2.5.59 with CONFIG_PACKET=m oopes when af_packet.ko is insmodded:
>  > 
>  > Unable to handle kernel paging request at virtual address 2220c021
>  >  printing eip:
>  > c0124011
>  > *pde = 00000000
>  > Oops: 0000
>  > CPU:    0
>  > EIP:    0060:[<c0124011>]    Not tainted
>  > EFLAGS: 00010097
>  > EIP is at __find_symbol+0x3d/0x7c
>  > eax: c020f70e   ebx: 00000536   ecx: 00000000   edx: c028b600
>  > esi: 2220c021   edi: e8889558   ebp: e8889558   esp: e67c5ecc
>  > ds: 007b   es: 007b   ss: 0068
>  > Process insmod (pid: 482, threadinfo=e67c4000 task=e6c80ce0)
>  > Stack: e8888f34 e8889a40 00000038 e8883f50 c0124960 e8889558 e67c5ef4 00000001 
>  >        e8888f34 e8889374 e67c5f28 c0124b2a e8883f50 00000016 e8889374 e8889558 
>  >        e8889a40 e8883f50 0000000c 00000017 e8889a40 00000000 0000007c c01253a4 
>  > Call Trace:
>  >  [<c0124960>] resolve_symbol+0x20/0x4c
>  >  [<c0124b2a>] simplify_symbols+0x82/0xe4
>  >  [<c01253a4>] load_module+0x5c4/0x7ec
>  >  [<c012562b>] sys_init_module+0x5f/0x194
>  >  [<c0108887>] syscall_call+0x7/0xb
> 
> This oops occurs for every module, not just af_packet.ko, at
> resolve_symbol()'s first call to __find_symbol().
> 
> What happens is that __find_symbol() oopses because the kernel's
> symbol table is in la-la land. (Note the bogus kernel adress
> 2220c021 it tried to dereference above.)
> 
> Reverting 2.5.59's patch to arch/i386/vmlinux.lds.S cured the
> problem and modules now load correctly for me.
> 
> I don't know if this is a problem also for non-i386 archs.
> 
> /Mikael

What version of ld are you using?

--
				Brian Gerst