Re: [Qemu-devel] [RFC 4/6] CLI: add -paused option

[Paolo Bonzini]

On 16/10/2017 18:59, Eduardo Habkost wrote:
>> +DEF("paused", HAS_ARG, QEMU_OPTION_paused, \
>> +    "-paused [state=]postconf|preconf\n"
>> +    "                postconf: pause QEMU after machine is initialized\n"
>> +    "                preconf: pause QEMU before machine is initialized\n",
>> +    QEMU_ARCH_ALL)
> I would like to allow pausing before machine-type is selected, so
> management could run query-machines before choosing a
> machine-type.  Would that need a third "-pause" mode, or will we
> be able to change "preconf" to pause before select_machine() is
> called?
> 
> The same probably applies to other things initialized before
> machine_run_board_init() that could be configurable using QMP,
> including but not limited to:
> * Accelerator configuration
> * Registering global properties
> * RAM size
> * SMP/CPU configuration

Should (or could) "-M none" be changed in a backwards-compatible way to
allow such preconfiguration?  For example

  qemu -M none -monitor stdio
  (qemu) machine-set-options pc,accel=kvm
  (qemu) c

Paolo