On 17/08/18 14:27, Mark Kettenis wrote:
>> Obviously I can't categorically state that QEMU's emulation is perfect,
>> but it can now reliably run all of Linux, MacOS, NetBSD and FreeBSD in
>> my local tests which makes me suspect that OpenBSD is trying to do
>> something different here.
>
> Runs fairly stable as long as there is enough RAM. There is an
> (unknown) pmap bug that causes memory corruption as soon as the
> machine starts swapping.
Right, I wonder if this is related to the invalid memory accesses I'm
seeing in QEMU? Fortunately it's fairly easy to boot different images
within the VM, so let's go backwards in time...
OpenBSD 6.1
- Boots to userspace, but hangs quickly at the installer shell
OpenBSD 6.0
- Hangs on boot just after the USB controller initialises
OpenBSD 5.9
- Boots to userspace, but hangs quickly at the installer shell (qemu
console logs attempt to execute a NULL opcode, so looks like we're
jumping off somewhere strange?)
OpenBSD 5.8
- Hangs on boot just after the USB controller initialises (qemu console
logs an attempt to execute an invalid/unsupported opcode: 00 - 1c - 17 -
0a (004ad5f8) 00000000 1)
OpenBSD 5.7
- Lots of "mac_intr_establish called, not yet inited" warnings in the
kernel dmesg output
- However it boots to userspace and the installer shell seems stable
OpenBSD 5.6
- Panics with a stack smash warning:
OpenBSD 5.6 (RAMDISK) #163: Fri Aug 8 09:05:59 MDT 2014
dera...@macppc.openbsd.org:/usr/src/sys/arch/macppc/compile/RAMDISK
real mem = 1073741824 (1024MB)
avail mem = 1029210112 (981MB)
warning: no entropy supplied by boot loader
mainbus0 at root: model PowerMac3,1
cpu0 at mainbus0: 7400 (Revision 0x209): 900 MHz: L2 cache not enabled
mem at mainbus0 not configured
mpcpcibr0 at mainbus0 pci: uni-north
pci0 at mpcpcibr0 bus 0
panic: smashed stack in ofw_enumerate_pcibus
Stopped at Debugger+0x10: lwz r0,36(r1)
00a00ae4: end+0x561cc fp a00ac0 nfp a00ae0
001ee6dc: panic+0xe0 fp a00ae0 nfp a00b40
001e235c: __stack_smash_handler+0x18 fp a00b40 nfp a00b60
0037ea18: ofw_enumerate_pcibus+0x1b0 fp a00b60 nfp a00bc0
0031bc90: pciattach+0xf0 fp a00bc0 nfp a00bf0
001e3e50: config_attach+0x1f0 fp a00bf0 nfp a00c40
0037dc0c: mpcpcibrattach+0x3b0 fp a00c40 nfp a00d60
001e3e50: config_attach+0x1f0 fp a00d60 nfp a00db0
003095f0: dbdma_flush+0x4d8 fp a00db0 nfp a00e90
001e3e50: config_attach+0x1f0 fp a00e90 nfp a00ee0
RUN AT LEAST 'trace' AND 'ps' AND INCLUDE OUTPUT WHEN REPORTING THIS PANIC!
DO NOT EVEN BOTHER REPORTING THIS WITHOUT INCLUDING THAT INFORMATION!
ddb> trace
00a00ae4: end+0x561cc fp a00ac0 nfp a00ae0
001ee6dc: panic+0xe0 fp a00ae0 nfp a00b40
001e235c: __stack_smash_handler+0x18 fp a00b40 nfp a00b60
0037ea18: ofw_enumerate_pcibus+0x1b0 fp a00b60 nfp a00bc0
0031bc90: pciattach+0xf0 fp a00bc0 nfp a00bf0
001e3e50: config_attach+0x1f0 fp a00bf0 nfp a00c40
0037dc0c: mpcpcibrattach+0x3b0 fp a00c40 nfp a00d60
001e3e50: config_attach+0x1f0 fp a00d60 nfp a00db0
003095f0: dbdma_flush+0x4d8 fp a00db0 nfp a00e90
001e3e50: config_attach+0x1f0 fp a00e90 nfp a00ee0
002f63ec: cpu_configure+0x24 fp a00ee0 nfp a00f00
001c525c: main+0x3f0 fp a00f00 nfp a00f40
001001bc: kernel_text+0xa8 fp a00f40 nfp 0
ddb> ps
PID PPID PGRP UID S FLAGS WAIT COMMAND
* 0 -1 0 0 7 0x10200 swapper
ddb>
OpenBSD 5.5
- Lots of "mac_intr_establish called, not yet inited" warnings in the
kernel dmesg output
- Panics on boot when initialising USB:
uhub0 at usb0 "Apple OHCI root hub" rev 1.00/1.00 addr 1
panic: trap type 600 at 2cf4a0 (mtx_enter+0x28) lr 2cf490
Stopped at Debugger+0x10: lwz r0,20(r1)
000000fc: tlbdsmsize+0x14 fp 94ba70 nfp 94ba80
001cec40: panic+0xd0 fp 94ba80 nfp 94bae0
002ce8cc: trap+0x184 fp 94bae0 nfp 94bb60
00100900: ddblow+0x1ac fp 94bb60 nfp 94bc10
002cf48c: mtx_enter+0x14 fp 94bc10 nfp 94bc20
001c4a50: config_attach+0x200 fp 94bc20 nfp 94bc60
00351018: mpcpcibrattach+0x3b0 fp 94bc60 nfp 94bd80
001c4a40: config_attach+0x1f0 fp 94bd80 nfp 94bdc0
002e4af0: mb_matchname+0x4e8 fp 94bdc0 nfp 94beb0
001c4a40: config_attach+0x1f0 fp 94beb0 nfp 94bef0
RUN AT LEAST 'trace' AND 'ps' AND INCLUDE OUTPUT WHEN REPORTING THIS PANIC!
DO NOT EVEN BOTHER REPORTING THIS WITHOUT INCLUDING THAT INFORMATION!
ddb> trace
000000fc: tlbdsmsize+0x14 fp 94ba70 nfp 94ba80
001cec40: panic+0xd0 fp 94ba80 nfp 94bae0
002ce8cc: trap+0x184 fp 94bae0 nfp 94bb60
00100900: ddblow+0x1ac fp 94bb60 nfp 94bc10
002cf48c: mtx_enter+0x14 fp 94bc10 nfp 94bc20
001c4a50: config_attach+0x200 fp 94bc20 nfp 94bc60
00351018: mpcpcibrattach+0x3b0 fp 94bc60 nfp 94bd80
001c4a40: config_attach+0x1f0 fp 94bd80 nfp 94bdc0
002e4af0: mb_matchname+0x4e8 fp 94bdc0 nfp 94beb0
001c4a40: config_attach+0x1f0 fp 94beb0 nfp 94bef0
002d1d9c: cpu_configure+0x24 fp 94bef0 nfp 94bf00
001a7314: main+0x3cc fp 94bf00 nfp 94bf40
001001bc: kernel_text+0xa8 fp 94bf40 nfp 0
ddb> ps
PID PPID PGRP UID S FLAGS WAIT COMMAND
* 0 -1 0 0 7 0x200 swapper
ddb>
OpenBSD 5.4-5.0
- Starts to boot, but VGA output stays black...?
- Lots of "mac_intr_establish called, not yet inited" warnings in the
kernel dmesg output
- Gets to userspace over serial but hangs mid-message
If we ignore the openpic warnings for the moment, something interesting
definitely happened between 5.7 and 5.8, since that's where I go from a
working userspace to something that hangs and often emits messages to
QEMU console about invalid opcodes (which generally means you've jumped
to the wrong or random bit of memory).
ATB,
Mark.
