On Sun, Dec 22, 2024 at 10:09:14PM +0100, Arnd Bergmann wrote: > On Sun, Dec 22, 2024, at 03:13, A. Wilcox wrote: > > On Dec 21, 2024, at 3:42 PM, Arnd Bergmann <arnd@xxxxxxxxxx> wrote: > > > > R0 .. R7 R8 .. R15 R16 .. R23 R24 .. R31 > > 00000000014a1124 0000000000000000 000000000135b4ac 0000000000000000 > > 000000000dc70f30 ffffffffc0000000 000000000dc70fa4 000000000173600c > > 0000000000000000 000000000e477010 0000000000000000 0000000000400000 > > ffffffff0141be4c 000000000149ab74 00000000ffffffff 0000000000000008 > > 00000000c0014b6c 0000000020000402 0000000040400000 00000000016f2000 > > ffffffff40400000 0000000000000000 0000000000000000 000000000dc70f60 > > 0000000000000000 0000000000000000 000000000e73d490 000000000149f000 > > 0000000000000000 000000000e756118 000000000dc70fa0 ffffffff40400000 > > > > CR / XER LR / CTR SRR0 / SRR1 DAR / DSISR > > 80000402 00000000014a1124 00000000014a1128 ffffffff0141be4c > > 0000000020040000 0000000000000000 8000000000003000 00000000 > > > > > > 2 > > > > > Which is the same thing that happens if you boot a 32-bit Linux kernel > > on a physical 64-bit Power machine. This is probably because KVM is > > so much more accurate than TCG for Power emulation :) > > Did you ask kvm to emulate a 32-bit platform though? Since the > register dump shows 64-bit registers, my guess is that this is the > result of trying to load a 32-bit kernel on "-machine pseries > -cpu native", which is not supported by the guest kernel. I would > expect that you need at least a 32-bit machine type (mac99, > pegasos2) and likely also a 32-bit CPU (7447a, e600). SLOF always shows 64-bit registers; SLOF only ever runs as 64-bit program. The *client* program can be 32-bit of course, but the dump of SRR1 here shows SF=1 (the top bit there). No idea what was running at the time, but something in the kernel I guess? (To show the last set client state, use ciregs .regs the thing exceptions print is via eregs .regs so you'll probably figure out the format ;-) ) If the client program is a 32-bit ELF file, SLOF starts the client program with SF=0. Segher
