runtime-rs: Add arm64 QEMU support

Add the necessary configuration and code changes to support QEMU
on arm64 architecture in runtime-rs.

Changes:
- Set MACHINETYPE to "virt" for arm64
- Add machine accelerators "usb=off,gic-version=host" required for
  proper arm64 virtualization
- Add arm64-specific kernel parameter "iommu.passthrough=0"
- Guard vIOMMU (Intel IOMMU) to skip on arm64 since it's not supported

These changes align runtime-rs with the Go runtime's arm64 QEMU support.

Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Signed-off-by: Kevin Zhao <kevin.zhao@linaro.org>

src/runtime-rs/Makefile

@@ -130,8 +130,23 @@ FCJAILERPATH = $(FCBINDIR)/$(FCJAILERCMD)
 FCVALIDJAILERPATHS = [\"$(FCJAILERPATH)\"]
 
 PKGLIBEXECDIR := $(LIBEXECDIR)/$(PROJECT_DIR)
+
+# EDK2 firmware names per architecture
+ifeq ($(ARCH), aarch64)
+    EDK2_NAME := aavmf
+endif
+
+# Set firmware paths from QEMUFW/QEMUFWVOL if defined
 FIRMWAREPATH :=
 FIRMWAREVOLUMEPATH :=
+ifneq (,$(QEMUCMD))
+    ifneq (,$(QEMUFW))
+        FIRMWAREPATH := $(PREFIXDEPS)/share/$(EDK2_NAME)/$(QEMUFW)
+    endif
+    ifneq (,$(QEMUFWVOL))
+        FIRMWAREVOLUMEPATH := $(PREFIXDEPS)/share/$(EDK2_NAME)/$(QEMUFWVOL)
+    endif
+endif
 
 ROOTMEASURECONFIG ?= ""
 KERNELTDXPARAMS += $(ROOTMEASURECONFIG)
@@ -374,6 +389,11 @@ ifneq (,$(QEMUCMD))
 ifeq ($(ARCH), s390x)
     VMROOTFSDRIVER_QEMU := virtio-blk-ccw
     DEFBLOCKSTORAGEDRIVER_QEMU := virtio-blk-ccw
+else ifeq ($(ARCH), aarch64)
+    # NVDIMM/virtio-pmem has issues on arm64 (cache coherency problems with DAX),
+    # so we use virtio-blk-pci instead.
+    VMROOTFSDRIVER_QEMU := virtio-blk-pci
+    DEFBLOCKSTORAGEDRIVER_QEMU := virtio-scsi
 else
     VMROOTFSDRIVER_QEMU := virtio-pmem
     DEFBLOCKSTORAGEDRIVER_QEMU := virtio-scsi

src/runtime-rs/arch/aarch64-options.mk

@@ -4,12 +4,16 @@
 # SPDX-License-Identifier: Apache-2.0
 #
 
-MACHINETYPE :=
+# ARM 64 settings
+
+MACHINETYPE := virt
 KERNELPARAMS := cgroup_no_v1=all systemd.unified_cgroup_hierarchy=1
-MACHINEACCELERATORS :=
+MACHINEACCELERATORS := usb=off,gic-version=host
 CPUFEATURES := pmu=off
 
 QEMUCMD := qemu-system-aarch64
+QEMUFW := AAVMF_CODE.fd
+QEMUFWVOL := AAVMF_VARS.fd
 
 # dragonball binary name
 DBCMD := dragonball

src/runtime-rs/crates/hypervisor/src/qemu/cmdline_generator.rs

@@ -2296,6 +2296,14 @@ impl<'a> QemuCmdLine<'a> {
     }
 
     fn add_iommu(&mut self) {
+        // vIOMMU (Intel IOMMU) is not supported on the "virt" machine type (arm64)
+        if self.machine.r#type == "virt" {
+            self.kernel
+                .params
+                .append(&mut KernelParams::from_string("iommu.passthrough=0"));
+            return;
+        }
+
         let dev_iommu = DeviceIntelIommu::new();
         self.devices.push(Box::new(dev_iommu));