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> > How does this function provide us the required quiescing ? > I do not see it revoking existing PFN/VFIO mapping or preventing a driver > from issueing a new access after cpu_cache_invalidate_memregion() > > Want to know what prevents new CXL.mem requests between cache invalidation > and reset completion ? > It does not require the range to be offline or unmapped first ? > > Best regards, > Richard Cheng. Hi Richard, You are right that request_mem_region() does not revoke PFN or VFIO mappings, and this series does not offline memory itself. It temporarily reserves every enabled HDM range and rejects the reset with -EBUSY if a conflicting resource owns one of those ranges. I documented this limitation explicitly in v12. -- Regards, Srirangan