Implement save/restore of the VGIC state using the newer KVM Device Control API. This requries some number of changes to existing code in addition to actually supporting save/restore of the necessary state.
The first patches (01-03) support creating the VGIC using the Device Control API. This change is necessary because there are no other suitable KVM APIs that we can leverage to access the VGIC state from user space and the device control API was crafted exactly for this purpose.
Subsequent patches add the missing infrastructure and user space API pieces necessary to actually save and restore the VGIC state. The GIC v2.0 architecture specification already specifies registers that can be used to save and restore the complete VGIC state for suspend/resume purposes on real hardware, and we can reuse this interface for the VGIC. The API is therefore based on the memory-mapped register accesses defined in the specs. See the individual patches for details.
The patches are based on kvm-arm-next with the arch timers save/restore patches applied: git://git.linaro.org/people/cdall/linux-kvm-arm.git timer-migrate-v4
This patch series based on the above can be cloned from: git://git.linaro.org/people/cdall/linux-kvm-arm.git vgic-migrate-v5
User space patches for QEMU have also been posted on the list, but an updated version is underway. Tested on Versatile Express TC2.
Changelogs in the individual patches.
Christoffer Dall (10): ARM: KVM: Allow creating the VGIC after VCPUs KVM: arm-vgic: Support KVM_CREATE_DEVICE for VGIC KVM: arm-vgic: Set base addr through device API irqchip: arm-gic: Define additional MMIO offsets and masks KVM: arm-vgic: Make vgic mmio functions more generic arm/arm64: kvm: Set vcpu->cpu to -1 on vcpu_put KVM: arm-vgic: Add vgic reg access from dev attr KVM: arm-vgic: Support unqueueing of LRs to the dist KVM: arm-vgic: Add GICD_SPENDSGIR and GICD_CPENDSGIR handlers KVM: arm-vgic: Support CPU interface reg access
Documentation/virtual/kvm/api.txt | 7 +- Documentation/virtual/kvm/devices/arm-vgic.txt | 73 ++++ arch/arm/include/uapi/asm/kvm.h | 8 + arch/arm/kvm/arm.c | 17 +- include/kvm/arm_vgic.h | 2 +- include/linux/irqchip/arm-gic.h | 12 + include/linux/kvm_host.h | 1 + include/uapi/linux/kvm.h | 1 + virt/kvm/arm/vgic.c | 583 +++++++++++++++++++++++-- virt/kvm/kvm_main.c | 5 + 10 files changed, 672 insertions(+), 37 deletions(-) create mode 100644 Documentation/virtual/kvm/devices/arm-vgic.txt