Explore kernel-level implementation of safe CXL cache support for Type2 devices in this 22-minute conference talk from the Linux Plumbers Conference. Examine the challenges of enabling CXL-capable devices to perform coherent read/write operations to host memory while maintaining security boundaries for virtual machines. Learn about the complexities that arise when devices access host memory through system cache coherency infrastructure, particularly regarding memory isolation for VMs controlling CXL devices. Discover the limitations of current IOMMU hardware for CXL cache accesses compared to traditional DMA operations, and investigate potential solutions including modifications to existing IOMMU APIs or the development of new safety mechanisms for secure CXL cache implementation.