Re: [PATCH v8 0/5] Mac Old World ROM experiment (ppc/mac_* clean ups and loading binary ROM)

[BALATON Zoltan via <qemu-devel@nongnu.org>]

On Sat, 17 Oct 2020, Mark Cave-Ayland wrote:
> On 16/10/2020 13:19, BALATON Zoltan via wrote:
>> On Fri, 16 Oct 2020, Mark Cave-Ayland wrote:
>>> On 16/10/2020 00:47, BALATON Zoltan via wrote:
>>>> This is the cut down version of the earlier series omitting unfinished
>>>> patches that I plan to rework later and rebased to Mark's qemu-macppc
>>>> branch. Compared to v7 the only change is the cast to (target_ulong)
>>>> from (uint32_t) as requested by Mark in patch 1.
>>> 
>>> FWIW the reason for suggesting the cast to target_ulong is so that the 
>>> same code works for both qemu-system-ppc and qemu-system-ppc64. For 
>>> qemu-system-ppc that should correctly drop the sign extension from 32-bit, 
>>> whilst still allowing someone to load a 64-bit ELF into qemu-system-ppc64 
>>> if requested.
>>> 
>>> Can you confirm that the sign extension behaviour is still correct for 
>>> both qemu-system-ppc and qemu-system-ppc64? If so I'm happy to give it a 
>>> R-B tag.
>> 
>> I've tried it now again with both ppc and ppc64: both OpenBIOS and a G3 
>> beige ROM can be loaded with qemu-system-ppc but qemu-system-ppc64 fails 
>> with OpenBIOS when casting to target_ulong (i think because target_ulong is 
>> 64 bit there but g3beige is still 32 bit but I haven't throughly debugged 
>> it). But everything works with my original uint32_t cast, so ditch it and 
>> use my original version. Should I resubmit or you can fix up? (I think I 
>> wait until it's clear if this will be taken by David or you and send a 
>> fixed version cc-ing David if this is decided to go through the PPC queue.)
>
> Hmmm yes I see that qemu-system-ppc64 fails because target_ulong will always 
> represent a 64-bit quantity, even if you request a 32-bit CPU. Rather than 
> add some CPU-specific code let's keep the uint32_t cast for now as I would 
> hope it is unlikely someone would load an ELF in high memory, and perhaps the 
> sign-extended address bug will get fixed later.
>
> With the cast reverted to uint32_t then for patches 1 and 2:
> Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
>
> If you can send a v9 with the cast fixed I'll apply this to my qemu-macppc 
> branch right away.

You could've really just edit the single cast in patch 1 before applying 
to change the it back but I've resent the changed patch 1 as v9 also 
adding your R-b for your convenience. Other patches are unchanged so you 
can take the v8 for those, I haven't resent those, let me know if you want 
the whole series but this is really getting much more work that it should 
be for such a simple change. (There is no cast in patch 2 as I've already 
stated several times.)

Regards,
BALATON Zoltan