On 04/25/2018 07:21 AM, Thomas Huth wrote: > The consoles ("sclpconsole" and "sclplmconsole") can only be configured > with "-device" and "-chardev" so far. Other machines use the convenience > option "-serial" to configure the default consoles, even for virtual > consoles like spapr-vty on the pseries machine. So let's support this > option on s390x, too. This way we can easily enable the serial console > here again with "-nodefaults", for example: > > qemu-system-s390x -no-shutdown -nographic -nodefaults -serial mon:stdio > > ... which is way shorter than typing: > > qemu-system-s390x -no-shutdown -nographic -nodefaults \ > -chardev stdio,id=c1,mux=on -device sclpconsole,chardev=c1 \ > -mon chardev=c1 > > The -serial parameter can also be used if you only want to see the QEMU > monitor on stdio without using -nodefaults, but not the console output. > That's something that is pretty impossible with the current code today: > > qemu-system-s390x -no-shutdown -nographic -serial none > > While we're at it, this patch also maps the second -serial option to the > "sclplmconsole", so that there is now an easy way to configure this second > console on s390x, too, for example: > > qemu-system-s390x -no-shutdown -nographic -serial null -serial mon:stdio > > Additionally, the new code is also smaller than the old one and we have > less s390x-specific code in vl.c :-) > > I've also checked that migration still works as expected by migrating > a guest with console output back and forth between a qemu-system-s390x > that has this patch and an instance without this patch. > > Signed-off-by: Thomas Huth <th...@redhat.com>
Very nice. I tested some combinations (only limited test) and everything looks good. Acked-by: Christian Borntraeger <borntrae...@de.ibm.com>