[PATCH v5 17/17] powerpc/32s: Enable CONFIG_VMAP_STACK

[Christophe Leroy]

On 02/07/2020 01:08 PM, Guenter Roeck wrote:
> On 2/7/20 12:28 AM, Christophe Leroy wrote:
>>
>>
>> On 02/07/2020 06:13 AM, Christophe Leroy wrote:
>>>
>>>
>>> Le 06/02/2020 à 21:31, Guenter Roeck a écrit :
>>>> On Sat, Dec 21, 2019 at 08:32:38AM +0000, Christophe Leroy wrote:
>>>>> A few changes to retrieve DAR and DSISR from struct regs
>>>>> instead of retrieving them directly, as they may have
>>>>> changed due to a TLB miss.
>>>>>
>>>>> Also modifies hash_page() and friends to work with virtual
>>>>> data addresses instead of physical ones. Same on load_up_fpu()
>>>>> and load_up_altivec().
>>>>>
>>>>> Signed-off-by: Christophe Leroy <christophe.leroy at c-s.fr>
>>>>
>>>> This patch results in qemu boot failures (mac99 with pmac32_defconfig).
>>>> Images fail silently; there is no console output. Reverting the patch
>>>> fixes the problem. Bisect log is attached below.
>>>>
>>>> Assuming this was tested on real hardware, am I correct to assume 
>>>> that qemu
>>>> for ppc32 (more specifically, qemu's mac99 and g3beige machines) no 
>>>> longer
>>>> works with the upstream kernel ?
>>>
>>> Before submitting the series, I successfully tested:
>>> - Real HW with powerpc 8xx
>>> - Real HW with powerpc 832x
>>> - Qemu's mac99
>>>
>>> I'll re-check the upstream kernel.
>>>
>>
>> This is still working for me with the upstream kernel:
>>
> 
> Interesting. What is your kernel configuration, your qemu version, and
> your qemu command line ?

Config is pmac32_defconfig + CONFIG_DEVTMPFS (But kernel also boots 
without CONFIG_DEVTMPFS)

QEMU emulator version 2.11.2

qemu-system-ppc -kernel vmlinux -M mac99 -initrd rootfs.cpio.gz -s -m 1024

Works with both GCC 5.5 and GCC 8.1

Christophe