tests/functional: Add a test for s390x pxelinux.cfg network booting

Check the various ways of booting a kernel via pxelinux.cfg file,
e.g. by specifying the config file name via the MAC address or the
UUID of the guest. Also check whether we can successfully load an
alternate kernel via the "loadparm" parameter here and whether the
boot menu shows up with "-boot menu=on".

Reviewed-by: Jared Rossi <jrossi@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20250709083443.41574-6-thuth@redhat.com>

3 files changed, 121 insertions, 0 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 1842c3d..e88ed2c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1805,6 +1805,7 @@ F: hw/s390x/ipl.*
 F: pc-bios/s390-ccw/
 F: pc-bios/s390-ccw.img
 F: docs/devel/s390-dasd-ipl.rst
+F: tests/functional/test_s390x_pxelinux.py
 T: git https://github.com/borntraeger/qemu.git s390-next
 L: qemu-s390x@nongnu.org
 
diff --git a/tests/functional/meson.build b/tests/functional/meson.build
index 050c900..1ae5f02 100644
--- a/tests/functional/meson.build
+++ b/tests/functional/meson.build
@@ -281,6 +281,7 @@ tests_rx_system_thorough = [
 
 tests_s390x_system_thorough = [
   's390x_ccw_virtio',
+  's390x_pxelinux',
   's390x_replay',
   's390x_topology',
   's390x_tuxrun',
diff --git a/tests/functional/test_s390x_pxelinux.py b/tests/functional/test_s390x_pxelinux.py
new file mode 100755
index 0000000..4fc33b8
--- /dev/null
+++ b/tests/functional/test_s390x_pxelinux.py
@@ -0,0 +1,119 @@
+#!/usr/bin/env python3
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Functional test that checks the pxelinux.cfg network booting of a s390x VM
+# (TFTP booting without config file is already tested by the pxe qtest, so
+#  we don't repeat that here).
+
+import os
+import shutil
+
+from qemu_test import QemuSystemTest, Asset, wait_for_console_pattern
+
+
+pxelinux_cfg_contents='''# pxelinux.cfg style config file
+default Debian
+label Nonexisting
+kernel kernel.notavailable
+initrd initrd.notavailable
+label Debian
+kernel kernel.debian
+initrd initrd.debian
+append testoption=teststring
+label Fedora
+kernel kernel.fedora
+'''
+
+class S390PxeLinux(QemuSystemTest):
+
+    ASSET_DEBIAN_KERNEL = Asset(
+        ('https://snapshot.debian.org/archive/debian/'
+         '20201126T092837Z/dists/buster/main/installer-s390x/'
+         '20190702+deb10u6/images/generic/kernel.debian'),
+        'd411d17c39ae7ad38d27534376cbe88b68b403c325739364122c2e6f1537e818')
+
+    ASSET_DEBIAN_INITRD = Asset(
+        ('https://snapshot.debian.org/archive/debian/'
+         '20201126T092837Z/dists/buster/main/installer-s390x/'
+         '20190702+deb10u6/images/generic/initrd.debian'),
+        '836bbd0fe6a5ca81274c28c2b063ea315ce1868660866e9b60180c575fef9fd5')
+
+    ASSET_FEDORA_KERNEL = Asset(
+        ('https://archives.fedoraproject.org/pub/archive'
+         '/fedora-secondary/releases/31/Server/s390x/os'
+         '/images/kernel.img'),
+        '480859574f3f44caa6cd35c62d70e1ac0609134e22ce2a954bbed9b110c06e0b')
+
+    def pxelinux_launch(self, pl_name='default', extra_opts=None):
+        self.require_netdev('user')
+        self.set_machine('s390-ccw-virtio')
+
+        debian_kernel = self.ASSET_DEBIAN_KERNEL.fetch()
+        debian_initrd = self.ASSET_DEBIAN_INITRD.fetch()
+        fedora_kernel = self.ASSET_FEDORA_KERNEL.fetch()
+
+        # Prepare a folder for the TFTP "server":
+        tftpdir = self.scratch_file('tftp')
+        shutil.rmtree(tftpdir, ignore_errors=True)   # Remove stale stuff
+        os.mkdir(tftpdir)
+        shutil.copy(debian_kernel, os.path.join(tftpdir, 'kernel.debian'))
+        shutil.copy(debian_initrd, os.path.join(tftpdir, 'initrd.debian'))
+        shutil.copy(fedora_kernel, os.path.join(tftpdir, 'kernel.fedora'))
+
+        pxelinuxdir = self.scratch_file('tftp', 'pxelinux.cfg')
+        os.mkdir(pxelinuxdir)
+
+        cfg_fname = self.scratch_file('tftp', 'pxelinux.cfg', pl_name)
+        with open(cfg_fname, 'w', encoding='utf-8') as f:
+            f.write(pxelinux_cfg_contents)
+
+        virtio_net_dev = 'virtio-net-ccw,netdev=n1,bootindex=1'
+        if extra_opts:
+                virtio_net_dev += ',' + extra_opts
+
+        self.vm.add_args('-m', '384',
+                         '-netdev', f'user,id=n1,tftp={tftpdir}',
+                         '-device', virtio_net_dev)
+        self.vm.set_console()
+        self.vm.launch()
+
+
+    def test_default(self):
+        self.pxelinux_launch()
+        # The kernel prints its arguments to the console, so we can use
+        # this to check whether the kernel parameters are correctly handled:
+        wait_for_console_pattern(self, 'testoption=teststring')
+        # Now also check that we've successfully loaded the initrd:
+        wait_for_console_pattern(self, 'Unpacking initramfs...')
+        wait_for_console_pattern(self, 'Run /init as init process')
+
+    def test_mac(self):
+        self.pxelinux_launch(pl_name='01-02-ca-fe-ba-be-42',
+                             extra_opts='mac=02:ca:fe:ba:be:42,loadparm=3')
+        wait_for_console_pattern(self, 'Linux version 5.3.7-301.fc31.s390x')
+
+    def test_uuid(self):
+        # Also add a non-bootable disk to check the fallback to network boot:
+        self.vm.add_args('-blockdev', 'null-co,size=65536,node-name=d1',
+                         '-device', 'virtio-blk,drive=d1,bootindex=0,loadparm=1',
+                         '-uuid', '550e8400-e29b-11d4-a716-446655441234')
+        self.pxelinux_launch(pl_name='550e8400-e29b-11d4-a716-446655441234')
+        wait_for_console_pattern(self, 'Debian 4.19.146-1 (2020-09-17)')
+
+    def test_ip(self):
+        self.vm.add_args('-M', 'loadparm=3')
+        self.pxelinux_launch(pl_name='0A00020F')
+        wait_for_console_pattern(self, 'Linux version 5.3.7-301.fc31.s390x')
+
+    def test_menu(self):
+        self.vm.add_args('-boot', 'menu=on,splash-time=10')
+        self.pxelinux_launch(pl_name='0A00')
+        wait_for_console_pattern(self, '[1] Nonexisting')
+        wait_for_console_pattern(self, '[2] Debian')
+        wait_for_console_pattern(self, '[3] Fedora')
+        wait_for_console_pattern(self, 'Debian 4.19.146-1 (2020-09-17)')
+
+
+if __name__ == '__main__':
+    QemuSystemTest.main()