On Mon, 27 Apr 2015 10:11:29 +0200 Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote: > > This patch implements the QMP command 'query-cpu-definitions' in the S390 > > context. The command returns a list of cpu definitions in the current host > > context. A runnable and migratable cpu model has the related attributes > > set to true. The order attribute is used to bring the listed cpu definitions > > in a release order. > > Can you add some explanation why we need the fallback code (e.g. something > along the line, when querying no KVM guest is available and to query the > capabilities we have to open a dummy VM bla bla) Maybe something like that: The returned values for attributes like runnable depend on the machine type QEMU is running on. The function kvm_s390_get_machine_props() is used to determine that. If QEMU was started for accelerator KVM, a KVMstate is established and machine properties are retrieved by cpu_model_get(). In case no KVMstate was established, e.g. during QEMU startup in daemonized mode with the default accelerator TCG, a fallback routine named get_machine_props_fallback() is used to retrieve the KVM machine properties. It first creates a temporary VM, performs the required ioctls and finally destroys the VM again. Michael -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
