dmesg | grep IOMMU
[    0.000000] DMAR: IOMMU enabled
[    0.120123] DMAR-IR: IOAPIC id 12 under DRHD base  0xeaffc000 IOMMU 6
[    0.120125] DMAR-IR: IOAPIC id 11 under DRHD base  0xe6bfc000 IOMMU 5
[    0.120126] DMAR-IR: IOAPIC id 10 under DRHD base  0xe27fc000 IOMMU 4
[    0.120127] DMAR-IR: IOAPIC id 18 under DRHD base  0xfbffc000 IOMMU 3
[    0.120128] DMAR-IR: IOAPIC id 17 under DRHD base  0xf7bfc000 IOMMU 2
[    0.120130] DMAR-IR: IOAPIC id 16 under DRHD base  0xf37fc000 IOMMU 1
[    0.120131] DMAR-IR: IOAPIC id 15 under DRHD base  0xef3fc000 IOMMU 0
[    0.120132] DMAR-IR: IOAPIC id 8 under DRHD base  0xde3fc000 IOMMU 7
[    0.120134] DMAR-IR: IOAPIC id 9 under DRHD base  0xde3fc000 IOMMU 7

Kvm guest:

[root@localhost ~]# lsmod |grep vfio
vfio_pci               41312  0
irqbypass              13503  1 vfio_pci
vfio_iommu_type1       22300  0
vfio                   32695  2 vfio_iommu_type1,vfio_pci
[root@localhost ~]# dmesg | grep IOMMU
[    0.000000] DMAR: IOMMU enabled
[root@localhost ~]# dpdk-devbind -b vfio-pci 00:08.0 00:09.0
Error: bind failed for 0000:00:08.0 - Cannot bind to driver vfio-pci
Error: unbind failed for 0000:00:08.0 - Cannot open /sys/bus/pci/drivers//unbind
[root@localhost ~]# tailf /var/log/messages
Aug 13 06:03:08 localhost kernel: VFIO - User Level meta-driver version: 0.3
Aug 13 06:04:15 localhost kernel: vfio-pci: probe of 0000:00:08.0 failed with error -22

kernel params:
[root@localhost ~]# cat /proc/cmdline
BOOT_IMAGE=/vmlinuz-3.10.0-862.9.1.el7.x86_64 root=/dev/mapper/rhel-root ro crashkernel=auto rd.lvm.lv=rhel/root rd.lvm.lv=rhel/swap rhgb quiet isolcpus=1-3 default_hugepagesz=1GB hugepagesz=1G hugepages=8 intel_iommu=on