Re: [RFC PATCH] tests/avocado: Test Xen guest support under KVM

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

Alex Bennée <alex.bennee@linaro.org> writes:

> From: David Woodhouse <dwmw@amazon.co.uk>
>
> Exercise guests with a few different modes for interrupt delivery. In
> particular we want to cover:
>
>  • Xen event channel delivery via GSI to the I/O APIC
>  • Xen event channel delivery via GSI to the i8259 PIC
>  • MSIs routed to PIRQ event channels
>  • GSIs routed to PIRQ event channels
>
> As well as some variants of normal non-Xen stuff like MSI to vAPIC and
> PCI INTx going to the I/O APIC and PIC, which ought to still work even
> in Xen mode.
>
> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
>
> ---
> v2 (ajb)
>   - switch to plain QemuSystemTest + LinuxSSHMixIn
>   - switch from fedora to custom kernel and buildroot
>   - removed some unused code
> TODO:
>   - properly probe for host support to skip test

So any idea for the best thing to check for here?

> ---
>  tests/avocado/kvm_xen_guest.py | 160 +++++++++++++++++++++++++++++++++
>  1 file changed, 160 insertions(+)
>  create mode 100644 tests/avocado/kvm_xen_guest.py
>
> diff --git a/tests/avocado/kvm_xen_guest.py b/tests/avocado/kvm_xen_guest.py
> new file mode 100644
> index 0000000000..1b4524d31c
> --- /dev/null
> +++ b/tests/avocado/kvm_xen_guest.py
> @@ -0,0 +1,160 @@
> +# KVM Xen guest functional tests
> +#
> +# Copyright © 2021 Red Hat, Inc.
> +# Copyright © 2023 Amazon.com, Inc. or its affiliates. All Rights Reserved.
> +#
> +# Author:
> +#  David Woodhouse <dwmw2@infradead.org>
> +#  Alex Bennée <alex.bennee@linaro.org>
> +#
> +# SPDX-License-Identifier: GPL-2.0-or-later
> +
> +import os
> +
> +from avocado_qemu import LinuxSSHMixIn
> +from avocado_qemu import QemuSystemTest
> +from avocado_qemu import wait_for_console_pattern
> +
> +class KVMXenGuest(QemuSystemTest, LinuxSSHMixIn):
> +    """
> +    :avocado: tags=arch:x86_64
> +    :avocado: tags=machine:q35
> +    :avocado: tags=accel:kvm
> +    :avocado: tags=kvm_xen_guest
> +    """
> +
> +    KERNEL_DEFAULT = 'printk.time=0 root=/dev/xvda console=ttyS0'
> +
> +    kernel_path = None
> +    kernel_params = None
> +
> +    # Fetch assets from the kvm-xen-guest subdir of my shared test
> +    # images directory on fileserver.linaro.org where you can find
> +    # build instructions for how they where assembled.
> +    def get_asset(self, name, sha1):
> +        base_url = ('https://fileserver.linaro.org/s/'
> +                    'kE4nCFLdQcoBF9t/download?'
> +                    'path=%2Fkvm-xen-guest&files=' )
> +        url = base_url + name
> +        # use explicit name rather than failing to neatly parse the
> +        # URL into a unique one
> +        return self.fetch_asset(name=name, locations=(url), asset_hash=sha1)
> +
> +    def common_vm_setup(self):
> +
> +        # TODO: we also need to check host kernel version/support
> +        self.require_accelerator("kvm")
> +
> +        self.vm.set_console()
> +
> +        self.vm.add_args("-accel", "kvm,xen-version=0x4000a,kernel-irqchip=split")
> +        self.vm.add_args("-smp", "2")
> +
> +        self.kernel_path = self.get_asset("bzImage",
> +                                          "367962983d0d32109998a70b45dcee4672d0b045")
> +        self.rootfs = self.get_asset("rootfs.ext4",
> +                                     "f1478401ea4b3fa2ea196396be44315bab2bb5e4")
> +
> +    def run_and_check(self):
> +        self.vm.add_args('-kernel', self.kernel_path,
> +                         '-append', self.kernel_params,
> +                         '-drive',  f"file={self.rootfs},if=none,id=drv0",
> +                         '-device', 'xen-disk,drive=drv0,vdev=xvda',
> +                         '-device', 'virtio-net-pci,netdev=unet',
> +                         '-netdev', 'user,id=unet,hostfwd=:127.0.0.1:0-:22')
> +
> +        self.vm.launch()
> +        self.log.info('VM launched, waiting for sshd')
> +        console_pattern = 'Starting dropbear sshd: OK'
> +        wait_for_console_pattern(self, console_pattern, 'Oops')
> +        self.log.info('sshd ready')
> +        self.ssh_connect('root', '', False)
> +
> +        self.ssh_command('cat /proc/cmdline')
> +        self.ssh_command('dmesg | grep -e "Grant table initialized"')
> +
> +    def test_kvm_xen_guest(self):
> +        """
> +        :avocado: tags=kvm_xen_guest
> +        """
> +
> +        self.common_vm_setup()
> +
> +        self.kernel_params = (self.KERNEL_DEFAULT +
> +                              ' xen_emul_unplug=ide-disks')
> +        self.run_and_check()
> +        self.ssh_command('grep xen-pirq.*msi /proc/interrupts')
> +
> +    def test_kvm_xen_guest_nomsi(self):
> +        """
> +        :avocado: tags=kvm_xen_guest_nomsi
> +        """
> +
> +        self.common_vm_setup()
> +
> +        self.kernel_params = (self.KERNEL_DEFAULT +
> +                              ' xen_emul_unplug=ide-disks pci=nomsi')
> +        self.run_and_check()
> +        self.ssh_command('grep xen-pirq.* /proc/interrupts')
> +
> +    def test_kvm_xen_guest_noapic_nomsi(self):
> +        """
> +        :avocado: tags=kvm_xen_guest_noapic_nomsi
> +        """
> +
> +        self.common_vm_setup()
> +
> +        self.kernel_params = (self.KERNEL_DEFAULT +
> +                              ' xen_emul_unplug=ide-disks noapic pci=nomsi')
> +        self.run_and_check()
> +        self.ssh_command('grep xen-pirq /proc/interrupts')
> +
> +    def test_kvm_xen_guest_vapic(self):
> +        """
> +        :avocado: tags=kvm_xen_guest_vapic
> +        """
> +
> +        self.common_vm_setup()
> +        self.vm.add_args('-cpu', 'host,+xen-vapic')
> +        self.kernel_params = (self.KERNEL_DEFAULT +
> +                              ' xen_emul_unplug=ide-disks')
> +        self.run_and_check()
> +        self.ssh_command('grep xen-pirq /proc/interrupts')
> +        self.ssh_command('grep PCI-MSI /proc/interrupts')
> +
> +    def test_kvm_xen_guest_novector(self):
> +        """
> +        :avocado: tags=kvm_xen_guest_novector
> +        """
> +
> +        self.common_vm_setup()
> +        self.kernel_params = (self.KERNEL_DEFAULT +
> +                              ' xen_emul_unplug=ide-disks' +
> +                              ' xen_no_vector_callback')
> +        self.run_and_check()
> +        self.ssh_command('grep xen-platform-pci /proc/interrupts')
> +
> +    def test_kvm_xen_guest_novector_nomsi(self):
> +        """
> +        :avocado: tags=kvm_xen_guest_novector_nomsi
> +        """
> +
> +        self.common_vm_setup()
> +
> +        self.kernel_params = (self.KERNEL_DEFAULT +
> +                              ' xen_emul_unplug=ide-disks pci=nomsi' +
> +                              ' xen_no_vector_callback')
> +        self.run_and_check()
> +        self.ssh_command('grep xen-platform-pci /proc/interrupts')
> +
> +    def test_kvm_xen_guest_novector_noapic(self):
> +        """
> +        :avocado: tags=kvm_xen_guest_novector_noapic
> +        """
> +
> +        self.common_vm_setup()
> +        self.kernel_params = (self.KERNEL_DEFAULT +
> +                              ' xen_emul_unplug=ide-disks' +
> +                              ' xen_no_vector_callback noapic')
> +        self.run_and_check()
> +        self.ssh_command('grep xen-platform-pci /proc/interrupts')


-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro