support/testing: add kmod runtime test

Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit 48790b43296f45aa7f9f8c6701e94fe86269c241)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

DEVELOPERS

@@ -1805,6 +1805,8 @@ F:	support/testing/tests/package/test_jq.py
 F:	support/testing/tests/package/test_jq/
 F:	support/testing/tests/package/test_kexec.py
 F:	support/testing/tests/package/test_kexec/
+F:	support/testing/tests/package/test_kmod.py
+F:	support/testing/tests/package/test_kmod/
 F:	support/testing/tests/package/test_kmscube.py
 F:	support/testing/tests/package/test_kmscube/
 F:	support/testing/tests/package/test_less.py

support/testing/tests/package/test_kmod.py

@@ -0,0 +1,97 @@
+import os
+
+import infra.basetest
+
+
+class TestKmod(infra.basetest.BRTest):
+    # This test uses the "virtio_net" driver compiled as a module. We
+    # need to recompile a Kernel for that.
+    kernel_fragment = \
+        infra.filepath("tests/package/test_kmod/linux-virtio-net.fragment")
+    config = \
+        f"""
+        BR2_aarch64=y
+        BR2_TOOLCHAIN_EXTERNAL=y
+        BR2_TARGET_GENERIC_GETTY_PORT="ttyAMA0"
+        BR2_LINUX_KERNEL=y
+        BR2_LINUX_KERNEL_CUSTOM_VERSION=y
+        BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="6.6.35"
+        BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
+        BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="board/qemu/aarch64-virt/linux.config"
+        BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="{kernel_fragment}"
+        BR2_PACKAGE_BUSYBOX_SHOW_OTHERS=y
+        BR2_PACKAGE_KMOD=y
+        BR2_PACKAGE_KMOD_TOOLS=y
+        BR2_TARGET_ROOTFS_EXT2=y
+        BR2_TARGET_ROOTFS_EXT2_4=y
+        # BR2_TARGET_ROOTFS_TAR is not set
+        """
+
+    def test_run(self):
+        drive = os.path.join(self.builddir, "images", "rootfs.ext4")
+        kern = os.path.join(self.builddir, "images", "Image")
+        self.emulator.boot(arch="aarch64",
+                           kernel=kern,
+                           kernel_cmdline=["root=/dev/vda console=ttyAMA0"],
+                           options=["-M", "virt",
+                                    "-cpu", "cortex-a57",
+                                    "-m", "256M",
+                                    "-drive", f"file={drive},if=virtio,format=raw"])
+        self.emulator.login()
+
+        # We check the kmod program can run. Busybox does not have a
+        # kmod applet, so there is no possible confusion.
+        self.assertRunOk("kmod --version")
+
+        # We check the "modprobe" is the one from kmod, rather than
+        # the Busybox applet version.
+        out, ret = self.emulator.run("modprobe --version")
+        self.assertEqual(ret, 0)
+        self.assertTrue(out[0].startswith("kmod version"))
+
+        # List modules with "kmod list", the virtio-net module should
+        # NOT be loaded yet.
+        out, ret = self.emulator.run("kmod list")
+        self.assertEqual(ret, 0)
+        self.assertNotIn("virtio_net", "\n".join(out))
+
+        # Get module info with modinfo.
+        out, ret = self.emulator.run("modinfo virtio-net")
+        self.assertEqual(ret, 0)
+        lsmod_out = "\n".join(out)
+        self.assertRegex(lsmod_out, r'name: *virtio_net')
+        self.assertRegex(lsmod_out, r'description: *Virtio network driver')
+
+        # With this test configuration, we are not supposed to have an
+        # eth0 Ethernet interface yet. Attempting to show info on this
+        # interface is expected to fail .
+        _, ret = self.emulator.run("ip link show dev eth0")
+        self.assertNotEqual(ret, 0)
+
+        # We try to load the module.
+        self.assertRunOk("modprobe virtio-net")
+
+        # We should now see the module in the list. This time, we use
+        # the "lsmod" command.
+        out, ret = self.emulator.run("lsmod")
+        self.assertEqual(ret, 0)
+        self.assertIn("virtio_net", "\n".join(out))
+
+        # The eth0 interface is supposed to be available, after the
+        # module loading. We configure the emulator user network to
+        # test the driver networking functionality. See:
+        # https://wiki.qemu.org/Documentation/Networking
+        self.assertRunOk("ip addr add dev eth0 10.0.2.15/24")
+        self.assertRunOk("ip link set dev eth0 up")
+
+        # We check we can ping the emulator.
+        ping_cmd = "ping -i 0.3 -c 2 10.0.2.2"
+        self.assertRunOk(ping_cmd)
+
+        # We check we can unload the driver.
+        self.assertRunOk("modprobe -r virtio-net")
+
+        # Now the driver is unloaded, we should no longer be able to
+        # ping the emulator.
+        _, ret = self.emulator.run(ping_cmd)
+        self.assertNotEqual(ret, 0)

support/testing/tests/package/test_kmod/linux-virtio-net.fragment

@@ -0,0 +1 @@
+CONFIG_VIRTIO_NET=m