VF doesn't work in guest when not pinned with "addr="

[Yongjie Ren]

Environment:
------------
Host OS (ia32/ia32e/IA64):All
Guest OS (ia32/ia32e/IA64):ia32e
Guest OS Type (Linux/Windows):Linux (rhel6 and rhel5u5)
kvm.git Commit:ef7c782ea4a99fafb3d60dc8b8c057e0ef14f9f7
qemu-kvm Commit:44755ea36fee3f0b1093ef27404def8857602274
Host Kernel Version:3.0.0+
Hardware: Westmere-EP platform

Bug detailed description:
--------------------------
SR-IOV VF NIC doesn't work in guest when not pinned pci address with "addr=x05". Guest's dmesg shows "Failed to initialize MSI-X interrupts." If not pinned an address with "addr=0x05", the VF will be pinned to "0000:00:03.0" by default, and that doesn't work.
Normal vtd NIC assignment doesn't have this issue.
commit:fda19064e of qemu-kvm.git is good.
commit:44755ea36 of qemu-kvm.git is bad with this issue.
There maybe something wrong between the two commit.
Here's some dmesg info in the guest.
----dmesg in guest------
Intel(R) Virtual Function Network Driver - version 1.0.0-k0
Copyright (c) 2009 Intel Corporation.
igbvf 0000:00:03.0: setting latency timer to 64
igbvf 0000:00:03.0: Failed to initialize MSI-X interrupts.
igbvf 0000:00:03.0: Intel(R) 82576 Virtual Function
igbvf 0000:00:03.0: Address: da:66:bb:e6:1e:f4
igbvf 0000:00:03.0: MAC: 1
....
igbvf 0000:00:03.0: Unable to allocate interrupt, Error: -1
....

Reproduce steps:
----------------
1.pci-stub the a VF in 82576 NIC
2.create a guest: qemu-system-x86_64 -m 1024 -smp 2 -device pci-assign,host=01:10.0 -net none -hda /root/rhel6.qcow
(if using '-device pci-assign,host=01:10.0,addr=0x5, the VF will work)
3.check network in guest

Current result:
----------------
VF doesn't work in guest.

Expected result:
----------------
VF works well in guest.

[Yongjie Ren (yongjie-ren)]

this bug doesn't exist in the latest qemu tree.