Hi Kamal, Jason, Running a version of ibv_devinfo compiled against an old rdma-core (ibv_devinfo from libibverbs-utils-16.2-3-fc28.x86_64 ) failed to run with rdma-core release 28.0 for qedr. The patch that caused this is commit c2841076 https://github.com/linux-rdma/rdma-core/commit/c28410765bdfe5cbed3cb2cdb1584eac3941469c#diff-8da8bc8b2790169de557d5dee83a278e c28410765bdf libibverbs: Fix incorrect return code ... The proper return code is EOPNOTSUPP when an operation is not supported. Signed-off-by: Kamal Heib <kamalheib1@xxxxxxxxx> The reason it failed is because qedr doesn't have a query_device_ex callback, so vctx->query_device_ex returns EOPNOTSUPP, and old libibverbs Compares the return code to ENOSYS I think applications compiled against old rdma-core should continue to run on new ones as well. Can this commit be reverted? Thanks, Michal
