Re: [PATCH v3] hw/pci/pci_bridge: ensure PCIe slots have only one slot

[Daniel P . Berrangé]

On Wed, Jul 20, 2022 at 01:25:55PM +0300, Roman Kagan wrote:
> It's possible to create non-working configurations by attaching a device
> to a derivative of PCIe slot (pcie-root-port, ioh3420, etc) and
> specifying a slot number other that zero, e.g.:
> 
>     -device pcie-root-port,id=s0,... \
>     -device virtio-blk-pci,bus=s0,addr=4,...
> 
> Make QEMU reject such configurations and only allow addr=0 on the
> secondary bus of a PCIe slot.

What do you mean by 'non-working' in this case.  The guest OS boots
OK, but I indeed don't see the device in the guest, but IIUC it was
said that was just because Linux doesn't scan for a non-zero slot.
That wouldn't be a broken config from QEMU's POV though, merely a
guest OS limitation ?  Or was there some other issue you see ?


With regards,
Daniel
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