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.
