Hiardware-Assisted Hypervisor (hv)

Emulated Peripherals and Devices

• Serial Port
• PCI
  • virtio-blk (legacy)
• PIC (Intel 8259)
• PIT (Intel 8254)
  • incomplete: injects IRQ #0 every 1ms regardless your settings
• APIC
  • incomplete: ignores all writes and does not support APIIC local timer

Supported Kernel Image Formats

• ELF
• ELF with Xen PVH

Tested Guest OS

• Resea
• Linux (config)

Running a hv

1. Use Linux with Nested VMX enabled.
2. Enable CONFIG_HYPERVISOR, HV_SERVER, RAMDISK_SERVER.
3. Run with VMX=y option:

make run VMX=y HV_GUEST_IMAGE=vmlinux.elf RAM_DISK_IMG=rootfs.ext4.img

Debugging Tips (on Linux KVM)

Enabling Trace Messages

echo 1 | sudo tee /sys/kernel/tracing/events/kvm/kvm_nested_vmexit/enable
echo 1 | sudo tee /sys/kernel/tracing/events/kvm/kvm_nested_intr_vmexit/enable
echo 1 | sudo tee /sys/kernel/tracing/events/kvm/kvm_nested_vmexit/enable
echo 1 | sudo tee /sys/kernel/tracing/events/kvm/kvm_nested_vmenter_failed/enable
echo 1 | sudo tee /sys/kernel/debug/tracing/tracing_on

Reading Trace Messages

sudo watch tail /sys/kernel/debug/tracing/trace