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

[BALATON Zoltan]

On Fri, 16 Oct 2020, Philippe Mathieu-Daudé wrote:
> On 10/16/20 11:58 AM, 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.
>
> IMO this is part of a bigger design problem. Not all
> machines main bus is 64-bit. I did some experiments
> but changing that involves a lot of work.

Did not want to reply to this to not bring it to your attention before 
patch gets in finally but it's too late...

Not sure what you refer to but in this particular case the problem only 
seems to be load_elf loading 32 bit ELF files returning sign extended 64 
bit address which looks bogus but since this function is widely used I did 
not feel confident enough to propose a patch to load_elf.

By the way, also the parameters of load_elf could take a clean up to 
remove all the mostly NULL values as I've pointed out before:

https://lists.nongnu.org/archive/html/qemu-devel/2019-01/msg03427.html

but all this could wait until later, these don't seem to be urgent 
problems to prevent moving mac machines forward now and could all be 
addressen in separate elf loading series. So just note the problem and 
move on for now please.

Reagards.
BALATON Zoltan