[libvirt] [PATCH 07/13] qemu: Add hotpluging support for PCI devices on S390 guests

[Yi Min Zhao]

在 2018/5/29 下午5:04, Cornelia Huck 写道:
> On Mon, 28 May 2018 16:26:57 +0800
> Xiao Feng Ren <renxiaof at linux.vnet.ibm.com> wrote:
>
>> On 5/25/2018 6:22 PM, Bjoern Walk wrote:
>>> Cornelia Huck <cohuck at redhat.com> [2018-05-24, 06:25PM +0200]:
>>>> On Thu, 24 May 2018 14:24:32 +0200
>>>> Xiao Feng Ren <renxiaof at linux.vnet.ibm.com> wrote:
>>>>   
>>>>> From: Yi Min Zhao <zyimin at linux.ibm.com>
>>>>>
>>>>> This commit adds hotplug support for PCI devices on S390 guests.
>>>>> There's no need to implement hot unplug for zPCI as QEMU implements
>>>>> an unplug callback which will unplug both PCI and zPCI device in a
>>>>> cascaded way.
>>>>> Currently, the following PCI devices are supported:
>>>>>     virtio-blk-pci
>>>>>     virtio-net-pci
>>>>>     virtio-rng-pci
>>>>>     virtio-input-host-pci
>>>>>     virtio-keyboard-pci
>>>>>     virtio-mouse-pci
>>>>>     virtio-tablet-pci
>>>>>     vfio-pci
>>>>>     Shmem device
>>>>>     SCSIVhost device
>>>> Hm, how did you arrive at this list? Is it 'anything that uses msi-x'?
>>> I guess it's just any device that libvirt actually supports hotplug for,
>>> with a few exceptions (cf. patch 3 and 6). Not familiar wuth msi-x.
>> The list should be the devices that support MSI-X and have realized the
>> hotplug in qemu,
>> we support the hotplug for them in the libvirt.  So the list will be
>> updated to:
>>
>>     virtio-blk-pci
>>     virtio-net-pci
>>     virtio-input-host-pci
>>     virtio-keyboard-pci
>>     virtio-mouse-pci
>>     virtio-tablet-pci
>>     vfio-pci
>>     SCSIVhost device
> Ok, that makes sense.
>
> I also checked that libvirt only allows setting the vectors property
> for virtio-serial and shmem (vectors == 0 turns msi-x off), so that
> should be fine.
>
>> As the model of Shmem is not support in qemu, the rng device doesn't
>> support MSI-X.  So remove them.
> So, should qemu add support for msi-x with virtio-rng-pci in the
> future, we'd want to update libvirt as well, correct?
>
>>
>> In addition, the bug found need to be fixed for the hotplug of tablet,
>> in the virDomainDeviceIsUSB()
>> if ((t == VIR_DOMAIN_DEVICE_DISK &&
>>            dev->data.disk->bus == VIR_DOMAIN_DISK_BUS_USB) ||
>>           (t == VIR_DOMAIN_DEVICE_INPUT &&
>>            dev->data.input->type == VIR_DOMAIN_INPUT_BUS_USB) ||
>> ---------->dev->data.input->bus == VIR_DOMAIN_INPUT_BUS_USB
>>           (t == VIR_DOMAIN_DEVICE_HOSTDEV &&
>> I will send the fix if this bug is agreed.
>>
>
I have not received my response mail until now....What's wrong?