Re: virtio-blk-pci chokes on some PCI slots

[Markus Armbruster <armbru@redhat.com>]

Markus Armbruster <armbru@redhat.com> writes:

> Even better: I can reproduce it with an unpatched upstream QEMU
> (qemu.git commit cfde4bd9) like this:
>
>     $ qemu foo.qcow2 -net nic -net nic -net nic -drive file=bar.img,if=virtio
>
> virtio-blk-pci ends up in slot 6.

And:

    $ qemu foo.qcow2 -net nic,model=virtio -net nic,model=virtio -net nic,model=virtio -net nic,model=virtio

chokes like this:

    Setting up hotplug.
    Creating block device nodes.
    Creating character device nodes.
    Loading virtio_pci module
    ACPI: PCI Interrupt Link [LNKC] enabled at IRQ 11
    virtio-pci 0000:00:03.0: PCI INT A -> Link[LNKC] -> GSI 11 (level, low) -> IRQ 11
    ACPI: PCI Interrupt Link [LNKD] enabled at IRQ 10
    virtio-pci 0000:00:04.0: PCI INT A -> Link[LNKD] -> GSI 10 (level, low) -> IRQ 10
    ACPI: PCI Interrupt Link [LNKA] enabled at IRQ 11
    virtio-pci 0000:00:05.0: PCI INT A -> Link[LNKA] -> GSI 11 (level, low) -> IRQ 11
    virtio-pci 0000:00:06.0: can't derive routing for PCI INT A
    virtio-pci 0000:00:06.0: PCI INT A: no GSI - using IRQ 9
    virtio-pci 0000:00:07.0: can't derive routing for PCI INT A
    virtio-pci 0000:00:07.0: PCI INT A: no GSI - using IRQ 11
    Loading virtio_blk module

Boot completes, but none of the four NICs work (no /dev/eth*).  If I use
only two, they end up in "good" slots, and both work fine.