Loading and executing kernel from a non-standard address using SY SLINUX

Loading and executing kernel from a non-standard address using SY SLINUX

[ravikumar.chakaravarthy]

I am trying to load and boot the kernel from a non-standard address
(0x200000). I am using the SYSLINUX boot loader, which loads the
kernel at that address. I have also made changes to the kernel to
setup code and startup_32() function to effect the same. When I boot
the system It says

Loading.......... Ready
Uncompressing Linux... OK Booting the kernel

and then hangs.

I guess the reason being the System.map entries are still using the
PAGE_OFFSET = 0xc0000000, as opposed to 0xc0100000.
I have the following questions??

1. How do i change the System.map to get the right PAGE_OFFSET.
2. Will it work if I load and boot the kernel from a different address
like (0xdf000000)??

3. Am I in the right track or missing something.

Thanks
  -Ravi

Re: Loading and executing kernel from a non-standard address using SY SLINUX

[Martin J. Bligh]

> I am trying to load and boot the kernel from a non-standard address
> (0x200000). I am using the SYSLINUX boot loader, which loads the
> kernel at that address. I have also made changes to the kernel to
> setup code and startup_32() function to effect the same. When I boot
> the system It says
> 
> Loading.......... Ready
> Uncompressing Linux... OK Booting the kernel
> 
> and then hangs.
> 
> I guess the reason being the System.map entries are still using the
> PAGE_OFFSET = 0xc0000000, as opposed to 0xc0100000.
> I have the following questions??
> 
> 1. How do i change the System.map to get the right PAGE_OFFSET.
> 2. Will it work if I load and boot the kernel from a different address
> like (0xdf000000)??
> 
> 3. Am I in the right track or missing something.

The kernel should decompress itself to the right space anyway ... check
arch/i386/boot/compressed/head.S ... should be minimal changes needed,
if any.

M.

Re: Loading and executing kernel from a non-standard address using SY SLINUX

[H. Peter Anvin]

Followup to:  <99F2150714F93F448942F9A9F112634CA54B07@txexmtae.amd.com>
By author:    ravikumar.chakaravarthy@amd.com
In newsgroup: linux.dev.kernel
>
> I am trying to load and boot the kernel from a non-standard address
> (0x200000). I am using the SYSLINUX boot loader, which loads the
> kernel at that address. I have also made changes to the kernel to
> setup code and startup_32() function to effect the same. When I boot
> the system It says
> 

Modified, perhaps.  Stock SYSLINUX loads at the standard address
(0x100000).

	-hpa
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