Re: [PATCH 3/3] powerpc/ppc64/kdump: better flag for running relocatable

Paul Mackerras
2008-10-23T03:44:17Z

Paul Mackerras writes:
> Milton Miller writes:
>
> > Move the flag to 0x5c, 1 word before the secondary cpu entry point at
> > 0x60. Use the copy at address 0 not the one in the base kernel image to
> > make it easier on kexec-tools.
>
> Why is it easier on kexec-tools? Doesn't kexec-tools know where it
> put the kernel?
>
> I'd much rather keep the flag inside the kdump kernel image, rather
> than having kexec/kdump start using random fixed locations outside the
> new kernel image.

In fact the cliching argument is that when the kernel is loaded by OF
or yaboot, we have no way to tell what will be at location 0x5c,
whereas we know that the word at offset 0x5c in the kernel image will
have been initialized to 0. So we had better put the flag inside the
kernel image.

Paul.