[Qemu-devel] SR-IOV PF reset and QEMU VFs VFIO passthrough

[Benoît Canet]

Hello,

I may have soon the PF driver of an SR-IOV card to code and make work with
QEMU/KVM so I have the following questions.

In an AMD64 setup where QEMU use VFIO to passthrough the VFs of an SR-IOV card
to a guest will the consequences of a PF FLR be handled fine by QEMU and the
guest ?

I read that pci_reset_function would call pci_restore_state restoring the SR-IOV
configuration after the reset of the PF.

The ways the hardware work means that the VFs would disappear and reappear in a
short lapse of time.

Will these events be handled by the kernel pci hotplug code ?

Given that the PF driver restore the PF config space after the reset will /sys
files used by QEMU disappear and reappear messing the QEMU VFIO passthrough or
will it goes smoothly ?

Best regards

Benoît Canet