Re: [PATCH 00/10] Fixes for DP8393X SONIC device emulation

[Finn Thain]

On Sat, 14 Dec 2019, Aleksandar Markovic wrote:

> On Saturday, December 14, 2019, Finn Thain <address@hidden>
> wrote:
> 
> > Hi All,
> >
> > There is a bug in the DP8393X emulation that can stop packet reception.
> >
> >
> Can you provide the details of your test scenario?
> 
> Thanks,
> Aleksandar
> 

I test the qemu build like this,

qemu-system-m68k -M q800 -m 512M -serial none -serial mon:stdio -g 800x600x4
-net nic,model=dp83932,addr=00:00:00:01:02:03
-net bridge,helper=/opt/qemu/libexec/qemu-bridge-helper,br=br0
-append "fbcon=font:ProFont6x11 console=tty0 console=ttyS0 ignore_loglevel"
-kernel vmlinux-4.14.157-mac-backport+
-initrd /mnt/loop/install/cdrom/initrd.gz

You can obtain this kernel binary from the linux-mac68k project on 
sourceforge. (I usually use a mainline Linux build but it makes no 
difference.)

I normally use a disk image with Debian/m68k SID rootfs but in this 
example I've used the initrd that you can find on the Debian/m68k 
installer ISO.

Once the guest starts, switch to a different virtual console and bring up 
the SONIC:

<ctrl>-<a> <ctrl>-<a> <2>
# ip addr add dev eth0 192.168.65.2/24
# ip link set dev eth0 up

On the host, send a ping flood (with preload) to the guest:

# ifconfig br0 192.168.65.1/24
# ping 192.168.65.2 -f -l 20

The packet reception ("deaf sonic") issue is reproduced immediately.

This has been observed in both qemu-m68k and mainline qemu. See also,
https://github.com/vivier/qemu-m68k/commit/0a45280c9fa40da8d5f30b1bb3d0513db91c3909