On Wed, Sep 03, 2025 at 10:19:31PM +0200, John Levon wrote:
> From: Mark Cave-Ayland <[email protected]>
>
> Add a basic test of the vfio-user PCI client implementation.
>
> Co-authored-by: John Levon <[email protected]>
> Signed-off-by: Mark Cave-Ayland <[email protected]>
> Signed-off-by: John Levon <[email protected]>
> ---
> MAINTAINERS | 1 +
> tests/functional/x86_64/meson.build | 1 +
> .../x86_64/test_vfio_user_client.py | 207 ++++++++++++++++++
> 3 files changed, 209 insertions(+)
> create mode 100755 tests/functional/x86_64/test_vfio_user_client.py
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 1ae28e8804..9987ac8a4d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4305,6 +4305,7 @@ F: docs/system/devices/vfio-user.rst
> F: hw/vfio-user/*
> F: include/hw/vfio-user/*
> F: subprojects/libvfio-user
> +F: tests/functional/x86_64/test_vfio_user_client.py
>
> EBPF:
> M: Jason Wang <[email protected]>
> diff --git a/tests/functional/x86_64/meson.build
> b/tests/functional/x86_64/meson.build
> index d0b4667bb8..eed1936976 100644
> --- a/tests/functional/x86_64/meson.build
> +++ b/tests/functional/x86_64/meson.build
> @@ -31,6 +31,7 @@ tests_x86_64_system_thorough = [
> 'replay',
> 'reverse_debug',
> 'tuxrun',
> + 'vfio_user_client',
> 'virtio_balloon',
> 'virtio_gpu',
> ]
> diff --git a/tests/functional/x86_64/test_vfio_user_client.py
> b/tests/functional/x86_64/test_vfio_user_client.py
> new file mode 100755
> index 0000000000..a9cb2f4621
> --- /dev/null
> +++ b/tests/functional/x86_64/test_vfio_user_client.py
> @@ -0,0 +1,207 @@
> + def prepare_images(self):
> + """Set up the images for the VMs."""
> + self.kernel_path = self.ASSET_KERNEL.fetch()
> + rootfs_path = self.ASSET_ROOTFS.fetch()
> +
> + self.server_rootfs_path = self.scratch_file('server.ext2')
> + shutil.copy(rootfs_path, self.server_rootfs_path)
> + os.chmod(self.server_rootfs_path, 0o600)
> + self.client_rootfs_path = self.scratch_file('client.ext2')
> + shutil.copy(rootfs_path, self.client_rootfs_path)
> + os.chmod(self.client_rootfs_path, 0o600)
So copying the read-only asset to a writable file in the scratchdir....
> +
> + def configure_server_vm_args(self, server_vm, sock_path):
> + """
> + Configuration for the server VM. Set up virtio-serial device backed
> by
> + the given socket path.
> + """
> + server_vm.add_args('-kernel', self.kernel_path)
> + server_vm.add_args('-append', 'console=ttyS0 root=/dev/sda')
> + server_vm.add_args('-drive',
> + f"file={self.server_rootfs_path},if=ide,format=raw,id=drv0")
> + server_vm.add_args('-snapshot')
..but here you're using -snapshot, so surely the copying of the asset
into the scratch dir is not required ?
> + server_vm.add_args('-chardev',
> +
> f"socket,id=sock0,path={sock_path},telnet=off,server=on,wait=off")
> + server_vm.add_args('-device', 'virtio-serial')
> + server_vm.add_args('-device',
> + 'virtserialport,chardev=sock0,name=org.fedoraproject.port.0')
> +
> + def configure_client_vm_args(self, client_vm, sock_path):
> + """
> + Configuration for the client VM. Point the vfio-user-pci device to
> the
> + socket path configured above.
> + """
> +
> + client_vm.add_args('-kernel', self.kernel_path)
> + client_vm.add_args('-append', 'console=ttyS0 root=/dev/sda')
> + client_vm.add_args('-drive',
> + f'file={self.client_rootfs_path},if=ide,format=raw,id=drv0')
...but no using of -snapshot here, so copying the asset would be
required?
Can we just use -snapshot in both cases & avoid the copying ?
> + client_vm.add_args('-device',
> + '{"driver":"vfio-user-pci",' +
> + '"socket":{"path": "%s", "type": "unix"}}' % sock_path)
> +
> + def setup_vfio_user_pci_server(self, server_vm):
> + """
> + Start the libvfio-user server within the server VM, and arrange
> + for data to shuttle between its socket and the virtio serial port.
> + """
> + wait_for_console_pattern(self, 'login:', None, server_vm)
> + exec_command_and_wait_for_pattern(self, 'root', '#', None, server_vm)
> +
> + exec_command_and_wait_for_pattern(self,
> + 'gpio-pci-idio-16 -v /tmp/vfio-user.sock >/var/tmp/gpio.out 2>&1
> &',
> + '#', None, server_vm)
> + # wait for libvfio-user to initialize properly
> + exec_command_and_wait_for_pattern(self, 'sleep 5', '#', None,
> server_vm)
> + exec_command_and_wait_for_pattern(self,
> + 'socat UNIX-CONNECT:/tmp/vfio-user.sock /dev/vport0p1,ignoreeof
> ' +
> + ' &', '#', None, server_vm)
Hardcoded socket paths in /tmp ...
> +
> + def test_vfio_user_pci(self):
> + self.prepare_images()
> + self.set_machine('pc')
> + self.require_device('virtio-serial')
> + self.require_device('vfio-user-pci')
> +
> + sock_dir = self.socket_dir()
> + socket_path = sock_dir.name + '/vfio-user.sock'
> + socket_path = '/tmp/vfio-user.sock'
This isn't honouring the temporary dir for the socket files.
This temp dir needs to be passed into setup_vfio_user_pci_server
> +
> + server_vm = self.get_vm(name='server')
> + server_vm.set_console()
> + self.configure_server_vm_args(server_vm, socket_path)
> +
> + server_vm.launch()
> +
> + self.log.debug('starting libvfio-user server')
> +
> + self.setup_vfio_user_pci_server(server_vm)
> +
> + client_vm = self.get_vm(name="client")
> + client_vm.set_console()
> + self.configure_client_vm_args(client_vm, socket_path)
> +
> + try:
> + client_vm.launch()
> + except:
> + self.log.error('client VM failed to start, dumping server logs')
> + exec_command_and_wait_for_pattern(self, 'cat /var/tmp/gpio.out',
> + '#', None, server_vm)
> + raise
> +
> + self.log.debug('waiting for client VM boot')
> +
> + wait_for_console_pattern(self, 'login:', None, client_vm)
> + exec_command_and_wait_for_pattern(self, 'root', '#', None, client_vm)
> +
> + #
> + # Here, we'd like to actually interact with the gpio device a little
> + # more as described at:
> + #
> + # https://github.com/nutanix/libvfio-user/blob/master/docs/qemu.md
> + #
> + # Unfortunately, the buildroot Linux kernel has some undiagnosed
> issue
> + # so we don't get /sys/class/gpio. Nonetheless just the basic
> + # initialization and setup is enough for basic testing of vfio-user.
> + #
> +
> + self.log.debug('collecting libvfio-user server output')
> +
> + out = exec_command_and_wait_for_pattern(self,
> + 'cat /var/tmp/gpio.out',
> + 'gpio: region2: wrote 0 to (0x1:1)',
> + None, server_vm)
> +
> + pattern = re.compile(r'^gpio:')
Use of 're' is overkill here...
> +
> + gpio_server_out = [s for s in out.decode().splitlines()
> + if pattern.search(s)]
...... as this can just use s.startswith("gpio:")
> +
> + for line in EXPECTED_SERVER_LINES:
> + if line not in gpio_server_out:
> + self.log.error(f'Missing server debug line: {line}')
> + self.fail(False)
> +
> +
> +if __name__ == '__main__':
> + QemuSystemTest.main()
> --
> 2.43.0
>
With regards,
Daniel
--
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