[RFC PATCH] tests/avocado: re-factor igb test to avoid timeouts

["Alex Bennée" <alex.bennee@linaro.org>]

The core of the test was utilising "ethtool -t eth1 offline" to run
through a test sequence. For reasons unknown the test hangs under some
configurations of the build on centos8-stream. Fundamentally running
the old fedora-31 cloud-init is just too much for something that is
directed at testing one device. So we:

  - replace fedora with a custom kernel + buildroot rootfs
  - rename the test from IGB to NetDevEthtool
  - re-factor the common code, add (currently skipped) tests for other
     devices which support ethtool
  - remove the KVM limitation as its fast enough to run in KVM or TCG

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Cc: Akihiko Odaki <akihiko.odaki@daynix.com>
---
 tests/avocado/igb.py            | 38 --------------
 tests/avocado/netdev-ethtool.py | 93 +++++++++++++++++++++++++++++++++
 2 files changed, 93 insertions(+), 38 deletions(-)
 delete mode 100644 tests/avocado/igb.py
 create mode 100644 tests/avocado/netdev-ethtool.py

diff --git a/tests/avocado/igb.py b/tests/avocado/igb.py
deleted file mode 100644
index abf5dfa07f..0000000000
--- a/tests/avocado/igb.py
+++ /dev/null
@@ -1,38 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0-or-later
-# ethtool tests for igb registers, interrupts, etc
-
-from avocado_qemu import LinuxTest
-
-class IGB(LinuxTest):
-    """
-    :avocado: tags=accel:kvm
-    :avocado: tags=arch:x86_64
-    :avocado: tags=distro:fedora
-    :avocado: tags=distro_version:31
-    :avocado: tags=machine:q35
-    """
-
-    timeout = 180
-
-    def test(self):
-        self.require_accelerator('kvm')
-        kernel_url = self.distro.pxeboot_url + 'vmlinuz'
-        kernel_hash = '5b6f6876e1b5bda314f93893271da0d5777b1f3c'
-        kernel_path = self.fetch_asset(kernel_url, asset_hash=kernel_hash)
-        initrd_url = self.distro.pxeboot_url + 'initrd.img'
-        initrd_hash = 'dd0340a1b39bd28f88532babd4581c67649ec5b1'
-        initrd_path = self.fetch_asset(initrd_url, asset_hash=initrd_hash)
-
-        # Ideally we want to test MSI as well, but it is blocked by a bug
-        # fixed with:
-        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=28e96556baca7056d11d9fb3cdd0aba4483e00d8
-        kernel_params = self.distro.default_kernel_params + ' pci=nomsi'
-
-        self.vm.add_args('-kernel', kernel_path,
-                         '-initrd', initrd_path,
-                         '-append', kernel_params,
-                         '-accel', 'kvm',
-                         '-device', 'igb')
-        self.launch_and_wait()
-        self.ssh_command('dnf -y install ethtool')
-        self.ssh_command('ethtool -t eth1 offline')
diff --git a/tests/avocado/netdev-ethtool.py b/tests/avocado/netdev-ethtool.py
new file mode 100644
index 0000000000..da0a22d51c
--- /dev/null
+++ b/tests/avocado/netdev-ethtool.py
@@ -0,0 +1,93 @@
+# ethtool tests for emulated network devices
+#
+# This test leverages ethtool's --test sequence to validate network
+# device behaviour.
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+import time
+
+from avocado import skip
+
+from avocado_qemu import QemuSystemTest
+from avocado_qemu import exec_command, exec_command_and_wait_for_pattern
+from avocado_qemu import wait_for_console_pattern
+
+class NetDevEthtool(QemuSystemTest):
+    """
+    :avocado: tags=arch:x86_64
+    :avocado: tags=machine:q35
+    """
+
+    KERNEL_COMMON_COMMAND_LINE = 'printk.time=0 root=/dev/sda console=ttyS0 '
+    # Runs in about 20s under KVM, 26s under TCG, 37s under GCOV
+    timeout = 45
+
+    def common_test_code(self, netdev, extra_args=None):
+        base_url = ('https://fileserver.linaro.org/s/'
+                    'kE4nCFLdQcoBF9t/download?'
+                    'path=%2Figb-net-test&files=' )
+
+        # This custom kernel has drivers for all the supported network
+        # devices we can emulate in QEMU
+        kernel_url = base_url + 'bzImage'
+        kernel_hash = '784daede6dab993597f36efbf01f69f184c55152'
+        kernel_path = self.fetch_asset(name="bzImage",
+                                       locations=(kernel_url), asset_hash=kernel_hash)
+
+        rootfs_url = base_url + 'rootfs.ext4'
+        rootfs_hash = '7d28c1bf429de3b441a63756a51f163442ea574b'
+        rootfs_path = self.fetch_asset(name="rootfs.ext4",
+                                       locations=(rootfs_url),
+                                       asset_hash=rootfs_hash)
+
+        kernel_params = self.KERNEL_COMMON_COMMAND_LINE
+        if extra_args:
+            kernel_params += extra_args
+
+        self.vm.add_args('-kernel', kernel_path,
+                         '-append', kernel_params,
+                         '-blockdev',
+                         f"driver=raw,file.driver=file,file.filename={rootfs_path},node-name=hd0",
+                         '-device', 'driver=ide-hd,bus=ide.0,unit=0,drive=hd0',
+                         '-device', netdev)
+
+        self.vm.set_console(console_index=0)
+        self.vm.launch()
+
+        wait_for_console_pattern(self, "Welcome to Buildroot", vm=None)
+        time.sleep(0.2)
+        exec_command(self, 'root')
+        time.sleep(0.2)
+        exec_command_and_wait_for_pattern(self,
+                                          "ethtool -t eth1 offline",
+                                          "The test result is PASS",
+                                          "The test result is FAIL")
+        time.sleep(0.2)
+        exec_command_and_wait_for_pattern(self, 'halt', "reboot: System halted")
+
+    # Skip testing for MSI for now. Allegedly it was fixed by:
+    #   28e96556ba (igb: Allocate MSI-X vector when testing)
+    # but I'm seeing oops in the kernel
+    @skip("Kernel bug with MSI enabled")
+    def test_igb(self):
+        self.common_test_code("igb")
+
+    def test_igb_nomsi(self):
+        self.common_test_code("igb", "pci=nomsi")
+
+
+    # It seems the other popular cards we model in QEMU currently fail
+    # the pattern test with:
+    #
+    #   pattern test failed (reg 0x00178): got 0x00000000 expected 0x00005A5A
+    #
+    # So for now we skip them.
+
+    @skip("Incomplete reg 0x00178 support")
+    def test_e1000(self):
+        self.common_test_code("e1000")
+
+    @skip("Incomplete reg 0x00178 support")
+    def test_i82550(self):
+        self.common_test_code("i82550")
-- 
2.39.2