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Date: Wed, 05 Nov 2008 07:57:38 +0100
From: Christian Franke <Christian.Franke@t-online.de>
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Robert Millan wrote:
>> ...
>> How do you treat differences in ABI ?
>>
>> Dis-allow loading of module with different value of ABI ? Or were you
>> planning that module itself adapts to different versions of GRUB 2 ABI's?
>>     
>
> The module itself could:
>
> GRUB_MOD_INIT(foo)
> {
>   if (grub_abi != GRUB_ABI)
>     {
>       grub_printf ("abi mismatch!\n");
>       return;
>     }
>
>   /* register our commands/terminals/disks/whatever */
> }
>
>   

Alternative: Export a symbol describing the ABI version in kernel 
("grub_abi_3_14"). Access this symbol in each module (this can be hidden 
in GRUB_MOD_INIT).

Then loading a module with wrong ABI version fails due to undefined symbol.

-- 
Christian Franke