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The presence of CXL.cache support for instance doesn't > actually mean the driver is going to enable it. However it is probably > harmless so lets go with this as path of least resistance. That same remark applies to ATS in general, we have no idea if the device is going to use it when turned on or not.. Generally Linux has taken the approach of almost always enabling ATS if the device offers the PCIe capability. The purpose of this series is to close of the few "almost" cases so it is always on. Jason