kernel since 5.6 do not boot anymore on Apple PowerBook

[Christophe Leroy]

Le 21/08/2020 à 15:50, Giuseppe Sacco a écrit :
> Il giorno ven, 21/08/2020 alle 15.29 +0200, Christophe Leroy ha
> scritto:
> [...]
>> 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 ?
> 
> Here it is. Not really the one on the video, but the last "skipped" for
> the same problem.
> https://eppesuigoccas.homedns.org/~giuseppe/christophe.tar.bz2
> 

Thanks.

The Oops in the video shows that the issue is at 0x1bcac and msr value 
shows that Instruction MMU is disabled. So this corresponds to address 
0xc001bcac. In the vmlinux you sent me this address is in 
power_save_ppc32_restore()

This issue is fixed by 
https://patchwork.ozlabs.org/project/linuxppc-dev/patch/7bce32ccbab3ba3e3e0f27da6961bf6313df97ed.1581663140.git.christophe.leroy@c-s.fr/

You also said in a previous mail that your original issue also happens 
when CONFIG_VMAP_STACK is not selected. The above bug being linked to 
CONFIG_VMAP_STACK, maybe it would be easier to bisect with 
CONFIG_VMAP_STACK unselected.

Christophe