Hi, Olivier, Recently, I've been working on this issue. https://github.com/OP-TEE/optee_os/issues/5943 <https://github.com/OP-TEE/optee_os/issues/5943 > Do you know any differences between hafnium's current implementation of fragment transmission while retrieving memory and the example process described in FF-A 1.1 Figure 18.4? Regards, Yuye.