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In real use case, config or any other ioctl should not come along > with VFIO_DEVICE_FEATURE_POWER_MANAGEMENT ioctl request. > > 2. Maintain some 'access_count' which will be incremented when we > do any config space access or ioctl. Please don't open code locks - if you need a lock then write a proper lock. You can use the 'try' variants to bail out in cases where that is appropriate. Jason