kernel since 5.6 do not boot anymore on Apple PowerBook

[Giuseppe Sacco]

Hello Cristophe,

Il giorno ven, 21/08/2020 alle 08.55 +0200, Christophe Leroy ha
scritto:
> Hi Giuseppe,
> 
> Le 08/07/2020 à 20:44, Christophe Leroy a écrit :
> > 
> > Le 08/07/2020 à 19:36, Giuseppe Sacco a écrit :
> > > Hi Cristophe,
> > > 
> > > Il giorno mer, 08/07/2020 alle 19.09 +0200, Christophe Leroy ha
> > > scritto:
[...]
> > > > What's the result with:
> > > > 
> > > > LANG=C make ARCH=powerpc CROSS_COMPILE=powerpc-linux- vmlinux
> > > 
> > > $ LANG=C make ARCH=powerpc CROSS_COMPILE=powerpc-linux- vmlinux
> > >    CALL    scripts/checksyscalls.sh
> > >    CALL    scripts/atomic/check-atomics.sh
> > >    CHK     include/generated/compile.h
> > >    CC      kernel/module.o
> > > kernel/module.c: In function 'do_init_module':
> > > kernel/module.c:3593:2: error: implicit declaration of function
> > > 'module_enable_ro'; did you mean 'module_enable_x'? [-Werror=implicit-
> > > function-declaration]
> > >   3593 |  module_enable_ro(mod, true);
> > >        |  ^~~~~~~~~~~~~~~~
> > >        |  module_enable_x
> > > cc1: some warnings being treated as errors
> > > make[1]: *** [scripts/Makefile.build:267: kernel/module.o] Error 1
> > > make: *** [Makefile:1735: kernel] Error 2
> > > 
> > > So, should I 'git bisect skip'?
> > 
> > Ah yes, I had the exact same problem last time I bisected.
> > 
> > So yes do 'git bisect skip'. You'll probably hit this problem half a 
> > dozen of times, but at the end you should get a usefull bisect anyway.
> > 
> 
> Were you able to progress ?

Very slowly. I am still working on it, currently at recompile #276.
git-bisect states that I have still about 700 commits to check, but the
real problem is that more than 60% of built kernels crash even before
displaying the cpu_freq message (probably another long lasting bug
hides the one I am looking for). All these skipped kernels make
bisecting very very slow.

A short video about the problem I face when I skip the build is here:
https://eppesuigoccas.homedns.org/~giuseppe/bug%20avvio%20powerbook%20g4.mp4

Bye,
Giuseppe