>-----Original Message-----
>From: Michal Prívozník <mprivozn@xxxxxxxxxx>
>Sent: Friday, April 14, 2023 9:06 PM
>To: Duan, Zhenzhong <zhenzhong.duan@xxxxxxxxx>; libvir-list@xxxxxxxxxx
>Cc: Peng, Chao P <chao.p.peng@xxxxxxxxx>
>Subject: Re: [PATCH v2] qemu: Fix domxml-to-native command failure
>
>On 4/14/23 07:34, Zhenzhong Duan wrote:
>> virsh command domxml-to-native failed with below error but start
>> command succeed for same domain xml.
>>
>> "internal error: invalid PCI passthrough type 'default'"
>>
>> If host PCI device's driver attribute isn't defined in domain xml,
>> qemu driver will choose a proper value based on host environment
>> before starting qemu process. But this is missed in domxml-to-native
>> command, add the same logic so domxml-to-native could pass and replace
>> the relevant code in qemuHostdevPreparePCIDevicesCheckSupport() with
>> an error report.
>>
>> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxx>
>> ---
>> v2: replace setting with an error report, suggested by Michal
>>
>> src/qemu/qemu_domain.c | 11 +++++++++++ src/qemu/qemu_hostdev.c |
>> 8 ++++----
>> 2 files changed, 15 insertions(+), 4 deletions(-)
>>
>> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index
>> 63b13b6875c9..517c90f93f0a 100644
>> --- a/src/qemu/qemu_domain.c
>> +++ b/src/qemu/qemu_domain.c
>> @@ -11274,6 +11274,17 @@
>qemuDomainPrepareHostdev(virDomainHostdevDef *hostdev,
>> }
>> }
>> }
>> + if (hostdev->mode == VIR_DOMAIN_HOSTDEV_MODE_SUBSYS &&
>> + hostdev->source.subsys.type ==
>VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_PCI) {
>> + bool supportsPassthroughVFIO =
>qemuHostdevHostSupportsPassthroughVFIO();
>> + virDomainHostdevSubsysPCIBackendType *backend =
>> + &hostdev->source.subsys.u.pci.backend;
>> +
>> + if (*backend == VIR_DOMAIN_HOSTDEV_PCI_BACKEND_DEFAULT &&
>> + supportsPassthroughVFIO &&
>> + virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DEVICE_VFIO_PCI))
>{
>> + *backend = VIR_DOMAIN_HOSTDEV_PCI_BACKEND_VFIO;
>> + }
>> + }
>>
>> return 0;
>> }
>> diff --git a/src/qemu/qemu_hostdev.c b/src/qemu/qemu_hostdev.c index
>> 45cd1066f0a5..305a323a0769 100644
>> --- a/src/qemu/qemu_hostdev.c
>> +++ b/src/qemu/qemu_hostdev.c
>> @@ -175,15 +175,15 @@
>qemuHostdevPreparePCIDevicesCheckSupport(virDomainHostdevDef
>**hostdevs,
>> case VIR_DOMAIN_HOSTDEV_PCI_BACKEND_DEFAULT:
>> if (supportsPassthroughVFIO &&
>> virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_VFIO_PCI)) {
>> - *backend = VIR_DOMAIN_HOSTDEV_PCI_BACKEND_VFIO;
>> + virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
>> + _("qemuDomainPrepareHostdev() should have set
>backend "
>> + "to
>> + VIR_DOMAIN_HOSTDEV_PCI_BACKEND_VFIO"));
>
>Ha! I've found one path where the backend is not set:
>qemuDomainAttachHostPCIDevice(). So we need a bit more code movement.
>But after that, this branch is effectively a dead code.
Oh, I see, the hot plug case.
>
>In fact, if we move things a bit a lot of code will become dead. So let me respin
>with more patches.
Thanks for doing that.
Regards
Zhenzhong
