kernel since 5.6 do not boot anymore on Apple PowerBook

[Christophe Leroy]

Hi again,

Le 21/08/2020 à 10:22, Giuseppe Sacco a écrit :
> 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
> 

Maybe the easiest would be first to locate this issue. Can you send me 
the vmlinux and the .config matching the Oops in the video ?

And also the output of git bisect log ?

Thanks
Christophe