On 02/10/2015 12:16, Peter Maydell wrote: > On 2 October 2015 at 11:05, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: >> On 02/10/2015 11:58, Peter Maydell wrote: >>> I definitely dislike the latter -- userspace ends up having to >>> emulate part of the CPU even though that CPU support is really >>> there in hardware. Also it requires us to edit the device tree, >>> which means it won't work at all on boards other than 'virt' >>> where we use the kernel's device tree rather than creating our >>> own. Better for the kernel to forward the timer >>> interrupts back out to userspace's irq controller. >> >> How do boards other than 'virt' work when emulated without KVM? It must >> be possible to emulate the physical timer in QEMU. > > Without KVM is easy -- we emulate the physical timer as just > one of the parts of the emulated CPU. With KVM, we don't emulate > the CPU at all. We don't try to handle a "half TCG half KVM" setup. I mean in the device tree. Does the boot loader realize it's under a hypervisor, and provide different device trees to the kernel? Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
