On Wed, Nov 19, 2014 at 02:08:08PM -0500, Don Slutz wrote: > > On 11/19/14 13:08, Paolo Bonzini wrote: > > > >On 19/11/2014 19:07, Don Slutz wrote: > >>>"-M pc -machine accel=xen" should work and, if that's what you want, > >>>disable the vmport device. I think this patch is wrong. > >>> > >>>Paolo > >>Well, I also want "-M pc -machine accel=xen,vmport=on" to work. > >Right. So let's start by deciding what the desired semantics are for > >all six cases: -M pc/xenfv, -machine vmport=on/off/absent. > > > >Paolo > > I get 12 cases (PCMachineState *pcms = PC_MACHINE(obj)):
We have more cases, if we consider "-M pc-2.1" too. With this first patch (the one changing default_machine_opts), I expect to get the following results: -M pc pcms->vmport is true -M pc -machine vmport=on pcms->vmport is true -M pc -machine vmport=off pcms->vmport is false -M pc-2.1 pcms->vmport is true -M pc-2.1 -machine vmport=on pcms->vmport is true (but it doesn't matter, QEMU 2.1 didn't have the vmport option) -M pc-2.1 -machine vmport=off pcms->vmport is false (but it doesn't matter, QEMU 2.1 didn't have the vmport option) -M xenfv pcms->vmport is false -M xenfv -machine vmport=on pcms->vmport is true -M xenfv -machine vmport=off pcms->vmport is false -M pc -machine accel=xen pcms->vmport is true -M pc -machine vmport=on,accel=xen pcms->vmport is true -M pc -machine vmport=off,accel=xen pcms->vmport is false -M pc-2.1 -machine accel=xen pcms->vmport is true ** -M pc-2.1 -machine vmport=on,accel=xen pcms->vmport is true (but it doesn't matter, QEMU 2.1 didn't have the vmport option) -M pc-2.1 -machine vmport=off,accel=xen pcms->vmport is false (but it doesn't matter, QEMU 2.1 didn't have the vmport option) -M xenfv -machine accel=xen pcms->vmport is false -M xenfv -machine vmport=on,accel=xen pcms->vmport is true -M xenfv -machine vmport=off,accel=xen pcms->vmport is false I believe there's no consensus yet about the one marked with "**" above. It boils to the question: do we need to keep guest ABI stability when using "-M pc-2.1 -machine accel=xen"? -- Eduardo