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Hi all,
   I have two hosts. Host1 run services of controller/compute/network, 
and host2 run services of compute. The network type is vlan.
   When creating port with direct type and booting a vm using this port 
on host2, the vm works well. But when create the vm on host1 using same 
way, the vm state is error. And the nova-compute log says:

ERROR nova.pci.stats [req-4af9b36d-8a0c-43d5-8535-fbf9e8d1b857 
06172a48a7254dda934a729f4a58d2ec 894880b2f31046d7b8a83bc3783df070 - - -] 
Failed to allocate PCI devices for instance. Unassigning devices back to 
pools. This should not happen, since the scheduler should have accurate 
information, and allocation during claims is controlled via a hold on 
the compute node semaphore

   Any suggestion will be grateful.
   Thanks.

   Yu