On Sun, Jul 19, 2020 at 2:21 PM Mark Cave-Ayland < mark.cave-ayl...@ilande.co.uk> wrote:
> On 19/07/2020 10:37, David VANTYGHEM wrote: > > >> I did a comparison with a couple of DT dumps I have around and I see > some Old World > >> Macs reserve up until 0x4000 and some New World Macs reserve up to > 0x3000 in low > >> memory, so I don't think this change should break anything. I should > add from looking > >> at the MMU translations I think this bug has been around ever since > grub was used, > >> and that up until now we just got lucky that nothing of any importance > in the PPC > >> vector table was being overwritten before now. > > > > debian-10.0-powerpc-NETINST-1.iso version 2019-07-16 and any other > > versions before are using GRUB 2.02+dfsg1-20 and boot. > > > > Versions after 2019-07-16 don't boot and are using GRUB 2.04-4. > > Hi David, > > Right, indeed - the important part is what you quoted from my email above: > "I think > this bug has been around ever since grub was used, and that up until now > we just got > lucky that nothing of any importance in the PPC vector table was being > overwritten > before now.". > > Without my proposed fix I still see the older grub images access those > low-level > pages but with different offsets, which just by luck happen not to > overwrite the MMU > handlers. > > Can you confirm that the test OpenBIOS I posted in my previous email at > https://www.ilande.co.uk/tmp/qemu/openbios-ppc-grubfix fixes the issue > for you? > > > ATB, > > Mark. > Hi, I gave the grub-based debian 10 image a go and it booted. The 5 MacOS/OSX images I tested also booted. You need to download the openbios and point to it on the command line with -bios openbios-ppc-grubfix Best, Howard
