Hi, I am testing sample_hsm/migin. After it catches a write event, it tries to clear managed regions by calling dm_set_region with DM_REGION_NOEVENT. It never returns from this call while the user write operation is suspended. It has the DM_RIGHT_EXCL before making the call, so there could be no access right problem. What's wrong? Thanks a lot. Francis [[HTML alternate version deleted]]