Re: Bug with Windows tap network when running qemu-system-ppc with Mac OS 9 guest

[Howard Spoelstra]

Hi Bin,
(I forgot to reply to all....)

> > In answer to your questions:
> >
> > 1. Yes, slirp works on Windows 10 with this setup.
> > 2. Yes, in Linux both tap and slirp work.
>
> Thanks! Just to be clear, the above testing was performed with commit
> 969e50b61a285b0cc8dea6d4d2ade3f758d5ecc7, right?
>

Yes, the test is based on current master, so including that commit.
As said, reverting it restores tap functionality in Windows.

> >
> > My Windows build is done with a fully up to date msys2 installation.
> >
> > I tried to debug in Windows:
> > (gdb) run
> > Starting program: c:\qemu-master-msys2\qemu-system-ppc.exe -L pc-bios
> > -M mac99 -m 128 -sdl -serial stdio -boot c -drive
> > "file=C:\Mac-disks\9.2-usb-pci-ddk.img,format=raw,media=disk" -device
> > "sungem,netdev=network01" -netdev "tap,ifname=TapQemu,id=network01" -S
> > [New Thread 13304.0x1f00]
> > [New Thread 13304.0x2f84]
> > [New Thread 13304.0x3524]
> > [New Thread 13304.0x2b8c]
> > [New Thread 13304.0x368c]
> > [New Thread 13304.0x3668]
> > [New Thread 13304.0xf4c]
> > [New Thread 13304.0x49c]
> > [New Thread 13304.0x1d4c]
> > [New Thread 13304.0x7fc]
> > [Thread 13304.0x7fc exited with code 0]
> > [New Thread 13304.0x357c]
> > [New Thread 13304.0x7c0]
> > [New Thread 13304.0x3564]
> > [New Thread 13304.0x26f4]
> > [New Thread 13304.0x2f68]
> >
> > Program received signal SIGSEGV, Segmentation fault.
> > 0x00007ffb9edea991 in ?? () from c:\qemu-master-msys2\libglib-2.0-0.dll
> > (gdb) bt
> > #0  0x00007ffb9edea991 in ?? () from c:\qemu-master-msys2\libglib-2.0-0.dll
> > #1  0x000800000480bf50 in ?? ()
> > Backtrace stopped: previous frame inner to this frame (corrupt stack?)
> > (gdb)
> >
> > Even before I could attach to the process.
>
> Is QEMU crashed, or the MacOS guest crashed?

Well, that is an interesting question.
qemu-system-ppc -M mac99 uses openbios and it crashes while still in
the openbios window just when it tries to boot the hd.
Besides Mac OS 9.2, I now also tried booting a Mac OS X 10.3 image and
it crashes just the same.

Tracing the default sungem network device shows:

C:\qemu-master-msys2>qemu-system-ppc.exe -L pc-bios -M mac99 -m 128
-sdl -serial stdio -boot c -drive
file=C:\Mac-disks\9.2-usb-pci-ddk.img,format=raw,media=
disk -device sungem,netdev=network01 -netdev
tap,ifname=TapQemu,id=network01 -trace "sung*"
sungem_reset Full reset (PCI:1)
sungem_rx_reset RX reset
sungem_tx_reset TX reset
sungem_reset Full reset (PCI:1)
sungem_rx_reset RX reset
sungem_tx_reset TX reset
sungem_rx_mac_disabled Check RX MAC disabled
sungem_rx_mac_disabled Check RX MAC disabled
sungem_rx_mac_disabled Check RX MAC disabled
sungem_mmio_mac_read MMIO mac read from 0x80 val=0x3456
sungem_mmio_mac_read MMIO mac read from 0x84 val=0x12
sungem_mmio_mac_read MMIO mac read from 0x88 val=0x5254

>> =============================================================
>> OpenBIOS 1.1 [Mar 16 2021 08:16]
>> Configuration device id QEMU version 1 machine id 1
>> CPUs: 1
>> Memory: 128M
>> UUID: 00000000-0000-0000-0000-000000000000
>> CPU type PowerPC,G4
milliseconds isn't unique.

Best,
Howard