Re: [PATCH v2 25/43] powerpc/32: Replace ASM exception exit by C exception exit from ppc64

[Michael Ellerman]

Christophe Leroy <christophe.leroy@xxxxxxxxxx> writes:
> Le 11/03/2021 à 14:46, Michael Ellerman a écrit :
>> Christophe Leroy <christophe.leroy@xxxxxxxxxx> writes:
>>> This patch replaces the PPC32 ASM exception exit by C exception exit.
>>>
>>> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
>>> ---
>>>   arch/powerpc/kernel/entry_32.S  | 481 +++++++++-----------------------
>>>   arch/powerpc/kernel/interrupt.c |   4 +
>>>   2 files changed, 132 insertions(+), 353 deletions(-)
>> 
>> Bisect points to this breaking qemu mac99 for me, with pmac32_defconfig.
>> 
>> I haven't had time to dig any deeper sorry.
>
> Embarrasing ...

Nah, these things happen.

> I don't get this problem on the 8xx (nohash/32) or the 83xx (book3s/32).
> I don't get this problem with qemu mac99 when using my klibc-based initramfs.
>
> I managed to reproduce it with the rootfs.cpio that I got some time ago from linuxppc github Wiki.

OK.

I'm using the ppc-rootfs.cpio.gz from here:

  https://github.com/linuxppc/ci-scripts/blob/master/root-disks/Makefile

And the boot script is:

  https://github.com/linuxppc/ci-scripts/blob/master/scripts/boot/qemu-mac99

I've been meaning to write docs on how to use those scripts, but haven't
got around to it.

There's nothing really special though it's just a wrapper around qemu -M mac99.

> I'll investigate it tomorrow.

Thanks.

cheers