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The method is not listed > + when CXL Reset would affect another CXL.cache or CXL.mem function. Not sure about CXL.cache, but as I replied to the cover letter, this last sentence is at least confusing. Only PF0 can enable/initialize CXL.mem so if there exists a memdev, any function using CXL will be affected ... but the reset can not happen because the range is in use by the PF0 initialization. If the reset can happen implies no PF is using it. > + > + Before issuing CXL Reset, the kernel quiesces the PCI function, > + rejects the operation if cached HDM state is unavailable or > + affected CXL memory is busy, invalidates CPU caches for enabled > + HDM ranges, disables CXL.cache, and initiates cache write-back > + where supported. After reset, the kernel restores PCI config > + state needed to access HDM MMIO, restores cached HDM decoder > + state, and completes PCI reset recovery. "cxl_reset" does not > + request CXL Reset Memory Clear. > + > What: /sys/bus/pci/devices/.../reset > Date: July 2009 > Contact: Michael S. Tsirkin