kernel since 5.6 do not boot anymore on Apple PowerBook

[Giuseppe Sacco]

Salut Cristophe,

Il giorno mer, 08/07/2020 alle 10.38 +0200, Christophe Leroy ha
scritto:
> Hi Giuseppe,
> 
> Le 08/07/2020 à 09:59, Giuseppe Sacco a écrit :
> > Hello Cristophe,
> > 
> > Il giorno mar, 07/07/2020 alle 17.34 +0200, Giuseppe Sacco ha
> > scritto:
[...]
> > > > And can you try without CONFIG_VMAP_STACK on 5.6.19
> > > 
> > > Sure, I'll let you know.
> > 
> > No, this change did not make the kernel boot. I only changed the
> > option
> > you proposed:
> > 
> > $ grep VMAP .config
> > CONFIG_HAVE_ARCH_VMAP_STACK=y
> > # CONFIG_VMAP_STACK is not set
> > 
> 
> Ok, at least it is not that. I wanted to be sure because this is a
> huge 
> change added recently that is selected by default.
> 
> I tried on QEMU with your config, it boots properly.
> 
> So I think the only way now will be to bisect. Hope you were able to 
> setup a cross compiler on a speedy machine.

thank you for your time; indeed I may now crosscompile the kernel in 15
minutes instead of about 390... I hope to have a final result in a
couple of days.

Bye,
Giuseppe