On 2011-07-25 13:48, Jan Kiszka wrote: > On 2011-07-25 13:39, Markus Armbruster wrote: >> Jan Kiszka <jan.kis...@siemens.com> writes: >> >>> On 2011-07-25 12:45, Richard W.M. Jones wrote: >>>> On Mon, Jul 25, 2011 at 12:33:01PM +0200, Jan Kiszka wrote: >>>>> On 2011-07-25 11:41, Richard W.M. Jones wrote: >>>>>> On Sat, Jul 23, 2011 at 12:38:37PM +0200, Jan Kiszka wrote: >>>>>>> From: Jan Kiszka <jan.kis...@siemens.com> >>>>>>> >>>>>>> -machine somehow suggests that it selects the machine, but it doesn't. >>>>>>> Fix that before this command is set in stone. >>>>>>> >>>>>>> Actually, -machine should supersede -M and allow to introduce arbitrary >>>>>>> per-machine options to the command line. That will change the internal >>>>>>> realization again, but we will be able to keep the user interface >>>>>>> stable. >>>>>> >>>>>> This breaks libguestfs which was doing: >>>>>> >>>>>> qemu -machine accel=kvm:tcg ... >>>>>> >>>>>> We are not passing any -M option at all. We don't particularly care >>>>>> about the machine type since we're not that performance sensitive and >>>>>> we don't need to serialize the machine state. >>>>>> >>>>>> I have checked, and this works: >>>>>> >>>>>> qemu -machine pc,accel=kvm:tcg ... >>>>>> >>>>>> "pc" is the default, right? What about for other architectures? >>>>> >>>>> Yes, pc is the right default. Other arch have other defaults. >>>> >>>> So what you're saying is we have to parse qemu -machine \? output by >>>> looking for the string '(default)'? eg: >>>> >>>> $ ./arm-softmmu/qemu-system-arm -machine \?|fgrep '(default)' >>>> integratorcp ARM Integrator/CP (ARM926EJ-S) (default) >>>> >>>> $ ./i386-softmmu/qemu -machine \?|fgrep '(default)' >>>> pc-0.14 Standard PC (default) >>> >>> I understand, this is clumsy. Will see if we can do better. >> >> Is there a technical reason why type isn't optional with -machine? >> >> [...] > > Maybe it's just the > > assert(!permit_abbrev || list->implied_opt_name); > > in qemu_opts_parse, but I haven't looked at all details (and all other > users) yet.
I was incorrectly pointing the core, the problem is solvable at the level where we parse -machine: -------8<-------- This allows to specify -machine options without setting an explicit machine type. We will pick the default machine in this case. Requesting the list of available machines is still possible via '-machine ?' e.g. Signed-off-by: Jan Kiszka <jan.kis...@siemens.com> --- vl.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-) diff --git a/vl.c b/vl.c index 8256504..5e53ddc 100644 --- a/vl.c +++ b/vl.c @@ -2720,7 +2720,10 @@ int main(int argc, char **argv, char **envp) fprintf(stderr, "parse error: %s\n", optarg); exit(1); } - machine = machine_parse(qemu_opt_get(opts, "type")); + optarg = qemu_opt_get(opts, "type"); + if (optarg) { + machine = machine_parse(optarg); + } break; case QEMU_OPTION_usb: usb_enabled = 1; -- 1.7.3.4