Re: [RFC] split floppy support off biosdisk

[Bean]

On Wed, Jun 18, 2008 at 1:23 AM, Javier Martín <address@hidden> wrote:
> El mar, 17-06-2008 a las 22:52 +0800, Bean escribió:
>> Hi,
>>
>> I think memory is not a problem here, as grub2 can use upper memory:
>>
>> src = raw data
>> dest = 0x100000
>> buf = dest + kernel_size
>>
> We could do that, but since the code would execute at the very first
> stages, where we still don't have a memory map, we could overwrite
> something important and wreak havoc. It's unlikely, since most computers
> have a wide space at 1MB with most or all of the RAM, before the ACPI
> structures and the BIOS area at the end. However, we should contemplate
> the possibility of things going awry and prepare to receive bug reports
> about failures on esoterically nonstandard computers, such as "GRUB
> triple-faults my HP Vectra 75".
> Alternatively, we could first check the BDA and, if we have enough
> "lower" memory for the operation, use it before venturing into post-1MB
> territory.
>
> I'm currently checking the memory requisites of LZMA decompression
> depending on the -1..9 compression setting, and will report back when
> finished

Hi,

Well, actually current lzo decompresser uses similar method,
decompress the data directly to 0x100000. The compressed kernel is
only used in i386-pc platform, and space at 0x100000 should be
available, as Linux kernel will be loaded at this address as well.

About lzma setting, although I can't be sure, but the default seems to
gain the best result.

-- 
Bean