Am 06.03.2013 um 10:58 schrieb Gleb Natapov <g...@redhat.com>:
> On Wed, Mar 06, 2013 at 10:40:18AM +0100, Paolo Bonzini wrote: >> Il 05/03/2013 16:25, Gleb Natapov ha scritto: >>>> 1) We need to set the generic interrupt type of the system before we >>>> create vcpus. >>>> >>>> This is a new ioctl that sets the overall system interrupt controller type >>>> to a specific model. This used so that when we create vcpus, we can create >>>> the appended "local interrupt controller" state without the actual >>>> interrupt controller device available yet. It is also used later to switch >>>> between interrupt controller implementations. >>>> >>>> This interrupt type is write once and frozen after the first vcpu got >>>> created. >>> >>> Why explicit ioctl is needed? Why not require specific irqchip to be >>> created before first vcpu. The device created determines system interrupt >>> controller type. >> >> QEMU creates CPUs before devices, and CPUs need to know what kind of >> local interrupt controller to create. Similar to how in-kernel LAPIC >> state is created long before the userspace device that proxies the LAPIC. > So what is the difference between calling this special ioctl before > creating vcpus and calling create device ioctl instead and create QEMU > proxy device at whatever point in time QEMU wants to create it? I don't understand the question really. What proxy device? Alex -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
