Hi, recently I was trying to play with the PCIe limits on the q35
machine type. I see that docs/pcie.txt mentions:
The IO space is very limited, to 65536 byte-wide IO ports, and may
even be fragmented by fixed IO ports owned by platform devices
resulting in at most 10 PCI Express Root Ports or PCI Express
Downstream Ports per system if devices with IO BARs are used in the
PCI Express hierarchy
But in my own experimental setup, I was able to successfully create and
power on a VM with 232 pcie-root-ports, with each root port hosting a
virtio-net device on it. The root ports, and the network devices end up
appearing inside the VM's PCI enumeration as well. So I'm left wondering
where this limit exactly come from? And I'm not sure if I am missing
something here, since I'm able to go way above the limit mentioned above.
regards,
tejus
