test: add boot test on arm64 as well

This commit enables arm64 boot tests for the generated image.

test/test_smoke.py

@@ -169,7 +169,6 @@ def test_image_is_generated(image_type):
         f"content: {os.listdir(os.fspath(image_type.img_path))}"
 
 
-@pytest.mark.skipif(platform.system() != "Linux", reason="boot test only runs on linux right now")
 @pytest.mark.parametrize("image_type", SUPPORTED_IMAGE_TYPES, indirect=["image_type"])
 def test_image_boots(image_type):
     with QEMU(image_type.img_path) as test_vm:

test/vm.py

@@ -1,5 +1,7 @@
 import abc
+import glob
 import pathlib
+import platform
 import subprocess
 import sys
 import uuid
@@ -85,32 +87,62 @@ class QEMU(VM):
     # TODO: support qemu-system-aarch64 too :)
     QEMU = "qemu-system-x86_64"
 
-    def __init__(self, img, snapshot=True):
+    def __init__(self, img, arch="", snapshot=True):
         super().__init__()
         self._img = pathlib.Path(img)
+        if arch in ("", "native"):
+            arch = platform.machine()
+        self._arch = arch
         self._qemu_p = None
         self._snapshot = snapshot
 
-    def start(self):
-        if self.running():
-            return
-        log_path = self._img.with_suffix(".serial-log")
-        self._ssh_port = get_free_port()
-        self._address = "localhost"
-        qemu_cmdline = [
-            self.QEMU, "-enable-kvm",
-            "-m", self.MEM,
-            # get "illegal instruction" inside the VM otherwise
+    def _find_ovmf_bios(self):
+        match self._arch:
+            case "arm64", "aarch64":
+                p = "/opt/homebrew/Cellar/qemu/*/share/qemu/edk2-aarch64-code.fd"
+                m = glob.glob(p)
+                if len(m) != 1:
+                    raise ValueError("cannot find edk2 bios in {p}: {m}")
+                return m[0]
+            case _:
+                raise ValueError("ovmf bios only supported on arm64 right now")
+
+    def _gen_qemu_cmdline(self):
+        qemu_cmdline_common = [
             "-cpu", "host",
             "-nographic",
             "-serial", "stdio",
             "-monitor", "none",
             "-netdev", f"user,id=net.0,hostfwd=tcp::{self._ssh_port}-:22",
             "-device", "rtl8139,netdev=net.0",
+            "-m", self.MEM,
         ]
         if self._snapshot:
-            qemu_cmdline.append("-snapshot")
-        qemu_cmdline.append(self._img)
+            qemu_cmdline_common.append("-snapshot")
+        qemu_cmdline_common.append(self._img)
+        match self._arch:
+            case "arm64", "aarch64":
+                return [
+                    "qemu-system-aarch64",
+                    "-M", "accel=hvf",
+                    "-machine", "virt",
+                    "-bios", self._find_ovmf_bios(),
+                ]
+            case "amd64", "x86_64":
+                return [
+                    "qemu-system-x86_64",
+                    "-M", "accel=kvm",
+                ] + qemu_cmdline_common
+            case _:
+                raise ValueError(f"unsupported architecture {self._arch}")
+
+    def start(self):
+        if self.running():
+            return
+        log_path = self._img.with_suffix(".serial-log")
+        self._ssh_port = get_free_port()
+        self._address = "localhost"
+        qemu_cmdline = self._gen_qemu_cmdline()
         self._log(f"vm starting, log available at {log_path}")
 
         # XXX: use systemd-run to ensure cleanup?