Re: [Qemu-devel] qemu-system-s390x command line

[Alexander Graf]

> Am 30.08.2015 um 22:11 schrieb Richard W.M. Jones <address@hidden>:
> 
> Hi Alex,
> 
> Do you or anyone have a working qemu-system-s390x command line I can
> use as a starting point to boot a [TCG] guest?
> 
> So far I have tried variations of:
> 
> ~/d/qemu/s390x-softmmu/qemu-system-s390x -M s390-ccw-virtio -m 1024 -smp 1 
> -drive file=s390x.img,if=none,id=disk0 -device 
> virtio-blk-ccw,drive=disk0,id=hd0,bootindex=1 -drive 
> file=Fedora-Server-DVD-s390x-22.iso

Ok, 2 problems here. I'm not sure the iso is bootable - you are definitely best 
off to just use -kernel until you have sonething working and then move on to 
booting without. CD boot is something real mainframes don't do very often, so 
it's a pretty unmaintained code path in installation media.

The other one is that we emulate most fancy new user level instructions of an 
ec12, but we only advertise ourselves as a z9 to the kernel. So you need to 
make sure that your kernel is compiled with support for old CPUs (RHEL7 for 
example is not).

Once you get past these points, things should be very self-explanatory. Oh - 
and -kernel is 0 overhead on s390x, unlike x86.


Alex

> ,if=none,id=disk1 -device virtio-blk-ccw,drive=disk1,id=hd1,bootindex=0 
> -serial stdio
> 
> Nothing seems to work at all ...
> 
> Rich.
> 
> -- 
> Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
> Read my programming and virtualization blog: http://rwmj.wordpress.com
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