ardavis> I was debugging this problem and when I added some debug ardavis> prints in mthca_tavor_arm_cq (cq.c), just before the ardavis> mthca_write64() call it started working. I will take a ardavis> closer look.... Ugh, smells like a compiler optimization problem or a timing problem. I'm still not seeing what could be going wrong, though. - R.