On Thu, Aug 05, 2021 at 01:58:53PM +0300, Leon Romanovsky wrote:

quoted

IMO, if ibv_rereg_mr failed, the mr is in undefined state, user
needs to call ibv_dereg_mr in order to release it, so there no
need to recover the original state.

The thing is that it undefined state in the kernel.  What will be if
user will change access_flags and try to use that "broken" MR
anyway? Will you catch it?

rereg is not atomic, if the rereg fails in the middle the mr should be
left in some safe state.

Jason