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Device ATC > invalidation timeout is a generic challenge across all IOMMU > architectures that support PCI ATS. Would it be feasible to implement a > common 'fencing and recovery' mechanism in the IOMMU core so that all > IOMMU drivers could benefit? I think yes, for parts, but the driver itself has to do something deep inside it's invalidation to allow the flush to complete without exposing the system to memory corruption - meaning it has to block translated requests before completing the flush I don't see how that can be made too generalized since we are running this flush stuff in irq and reclaim contexts, it has to be very small and targtted without memory allocation or sleeping locks. Jason