Re: Kernel 6.9 fails to boot with "can't boot dump kernel from OF"

> On 6 Jul 2024, at 17:26, Reimar Döffinger <[email protected]> wrote:
> 
> 
>> On 6 Jul 2024, at 17:17, John Paul Adrian Glaubitz <[email protected]> wrote:
>> 
>> Hi Reimar,
>> 
>>> On Jul 6, 2024, at 5:09 PM, Reimar Döffinger <[email protected]> wrote:
>>> 
>>> Hi!
>>> The newest 6.9 powerpc kernel build seems to be incompatible with OpenFirmware boot,
>>> so boot fails on my PowerPC macMini.
>>> The error message is
>>> "Error: You can't boot a kdump kernel from OF!"
>>> The error message seems not entirely accurate, it seems the issue is that
>>> CONFIG_PHYSICAL_START
>>> is no longer 0, which probably comes from
>>> CONFIG_CRASH_DUMP=y
>>> being set.
>>> Can this be reverted?
>> 
>> Could you verify that this change actually fixes the problem? This would save me some work.
> 
> I checked the kernel source, the error message is under a if (PHYSICAL_START > 0), so that I am quite certain is the issue.
> Actually testing means compiling the kernel, which will take quite some while.

I can at least confirm that unsetting CONFIG_CRASH_DUMP in menuconfig results in CONFIG_PHYSICAL_START to revert to 0.
So it seems very likely that this single config setting is the root cause.