Re: [PATCH] x86: put initial_pg_tables into bss -v2

From: Yinghai Lu
Date: Sun Mar 01 2009 - 12:50:44 EST


H. Peter Anvin wrote:
> Yinghai Lu wrote:
>> Impact: cleanup
>>
>> Don't use ram after _end blindly for pagetables.
>> put those pg table into bss
>>
>> also remove init_pg_tables_start/end tricks all around
>>
>> v2: keep initial page table up to 512M only.
>>
>
> I really, REALLY, don't like this. This is going right back to the
> situation which we had before the dynamically generated page tables. We
> now have yet another hardcoded limit, and big chunk of wasted memory in
> case we don't need to allocate it all.

that limit is there in for 64 too. aka 512M direct mapping. (need 1Mbytes space for page tables)

we can get rid of that limit: with careful link sequence to make sure that code init_memory_mapping and before is some fixed range.

YH
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/