Maximum bootable kernel size in current ARM linux

[Haojian Zhuang]

On Mon, Sep 13, 2010 at 4:43 PM, Marek Vasut <marek.vasut at gmail.com> wrote:
> Dne Po 13. září 2010 09:40:56 Bruce M. Penrod napsal(a):
>> This seems like a pretty straightforward question, but extensive web
>> searching hasn't shown a really clear, up-to-date answer.  The most
>> recent info is circa 2004 and states that 4MB is the largest
>> uncompressed ARM kernel that may be loaded.  Not being an ARM assembly
>> guru (head.S baffles me), I'd like to know if that is still true in
>> 2010, and if it is, why?
>>
>> I'm having one hell of a time compiling a monolithic kernel and keeping
>> it under 4M without leaving out some core networking features I need.
>>  From my searching, it looks like x86 has either removed the limit or
>> raised it to a much higher number.  It's not clear to me why a 32 bit
>> processor would not be able to boot a kernel larger than 4 MB.
>
> Hey, CCed Russell.
>
> Btw. this shouldn't be true anymore. On the other hand, why do you need such a
> huge kernel?
>
> It's not even possible to create kernel that big if you don't have some kind of
> initramfs in, right? Besides, you can use some kind of a compression, like LZMA
> or something to keep the size down.
>
> Cheers

If initramfs is built in, we'll get a huge kernel. Even using LZMA, my
kernel size is near 5MB.