Re: [Qemu-devel] regression: target/ppc: convert VSX logical operations to vector operations broke X for ppc64le guest

[Mark Cave-Ayland]

On 28/02/2019 08:39, Andrew Randrianasulu wrote:

>>> configure line:
>>> setarch i686 ./configure --target-list=ppc64-softmmu
>>>
>>> launch line:
>>> ppc64-softmmu/qemu-system-ppc64 -display
>>> sdl,gl=on -hda /mnt/sdb1/PPC-img/alpine_disk.img
>>>
>>> where alpine_disk.img is HDD installed Alpine 3.7 for ppc64le with xfce4
>>> desktop.
>>
>> AFAICT the vector instructions converted here are independent of endian, so
>> I can't see why this patch on its own would have any effect.
>>
>> Maybe it could be because the "setarch i686" part forces use of some
>> lesser-used 32-bit paths in the vector code - is this required? And do you
>> see the same issue on a x86_64 build?
> 
> I use 32-bit Slackware userland with x86_64 kerenl - so setarch prevent most 
> of 
> configures from detecting my arch wrongly.
> 
> Yes, bug was and is present with qemu compiled for x86_64 (inside chroot).
> I initially discovered it there, and after dropping -O3 and even 
> march=native, 
> and even disabling avx2 via configure switch - moved to bisect.
> 
> https://lists.gnu.org/archive/html/qemu-devel/2019-02/msg06414.html

Can you upload your alpine_disk.img somewhere and then email me the link 
off-list?
I'll see if I can take a look when I get a spare moment.


ATB,

Mark.