Some systems out there (well, one type in particular - the Raspberry Pi series) do have virtualization capabilities in the core, but no ARM GIC interrupt controller. To run on these systems, the cleanest route is to just handle all interrupt delivery in user space and only deal with IRQ pins in the core side in KVM. This works pretty well already, but breaks when the guest starts to use architected timers, as these are handled straight inside kernel space today. This patch set allows user space to receive vtimer events as well as mask them, so that we can handle all vtimer related interrupt injection from user space, enabling us to use architected timer with user space gic emulation. I have successfully run edk2 as well as Linux using these patches on a Raspberry Pi 3 system with acceptable speed. A branch with WIP QEMU code can be found here: https://github.com/agraf/qemu.git no-kvm-irqchip To use the user space irqchip, just run it with $ qemu-system-aarch64 -M virt ... if you're on a non-vgic host system. Or -M virt,kernel-irqchip=off if your host system has vgic support. v1 -> v2: - Add back curly brace that got lost v2 -> v3: - Fix "only only" in documentation - Split patches - Remove kvm_emulate.h include v3 -> v4: - Improve documentation Alexander Graf (2): KVM: arm/arm64: Add vcpu ENABLE_CAP functionality KVM: arm/arm64: Route vtimer events to user space Documentation/virtual/kvm/api.txt | 34 ++++++++++- arch/arm/include/asm/kvm_host.h | 3 + arch/arm/kvm/arm.c | 47 +++++++++++--- arch/arm64/include/asm/kvm_host.h | 3 + include/uapi/linux/kvm.h | 14 +++++ virt/kvm/arm/arch_timer.c | 125 +++++++++++++++++++++++++++----------- 6 files changed, 183 insertions(+), 43 deletions(-) -- 1.8.5.6 -- 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
