Merge tag 'iommu-fixes-for-v3.13-rc4' of git://github.com/awilliam/linux-vfio
Pull iommu fixes from Alex Williamson:
"arm/smmu driver updates via Will Deacon fixing locking around page
table walks and a couple other issues"
* tag 'iommu-fixes-for-v3.13-rc4' of git://github.com/awilliam/linux-vfio:
iommu/arm-smmu: fix error return code in arm_smmu_device_dt_probe()
iommu/arm-smmu: remove potential NULL dereference on mapping path
iommu/arm-smmu: use mutex instead of spinlock for locking page tables