Qemu 2.6 Solaris 8 Sparc telnet terminate itself

With Qemu 2.6, Solaris 8 can be installed and run. However, it sometimes terminate itself with I/O thread spun for 1000 iterations. 

qemu-system-sparc -nographic -monitor null -serial mon:telnet:0.0.0.0:3000,server -hda ./Sparc8.disk -m 256 -boot c -net nic,macaddr=52:54:0:12:34:56 -net tap,ifname=tap0,script=no,downscript=noQEMU waiting for connection on: disconnected:telnet:0.0.0.0:3000,server
main-loop: WARNING: I/O thread spun for 1000 iterations