Subject: Re: Patch boot/common/relocate.S to start kernel at 0x000c

From: "Dale Farnsworth" <[email-masked]>
Date: Tue, 4 Mar 2003 21:28:34 -0700

On Wed, Mar 05, 2003 at 02:24:32AM +0000, Paul Mackerras wrote:
> Wolfgang Denk writes:
>
> > BTW: _all_ this writing to kernel text is a Bad  Thing  (TM),  as  it
> > makes XIP (for example running from ROM) really difficult.
>
> Well, there is no reason why the secondary hold code shouldn't just
> reference an ordinary variable in the kernel data section.  It would
> take a couple more instructions, but that shouldn't be a problem.  The
> starting address for the secondary hold code needs to be well-known
> (at least to the prep boot wrapper) but the variable that it spins on
> doesn't.
>
> Paul.

Well, that does add the requirement that kernel data be mapped at its
linked-at address before __secondary_hold references said variable.

By the way, the recent addition of the call to smp_call_init_cpu,
places the same requirement on __secondary_start, unfortunately.

-Dale

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