I am trying to use memory windows and I am getting EPERM (errno=1) when calling ibv_alloc_mw (with both types of MWs).
I have mellanox ConnectX-3 cards and the following OFED:
ofed_info | head -n 1
MLNX_OFED_LINUX-3.2-2.0.0.0 (OFED-3.2-2.0.0):
It seems my card should support this capability:
ibv_devinfo -v | grep EXP_MW
EXP_MW_TYPE_2B
EXP_MW_TYPE_2B
When running rping in the Mellanox OFED I get the same error:
librdmacm-1.1.0mlnx/examples> ./rping -s &
librdmacm-1.1.0mlnx/examples> ./rping -c -a 10.10.49.87 -w 1
rdma_buf alloc_mw failed
rping_setup_buffers failed: -12
librdmacm-1.1.0mlnx/examples> ./rping -c -a 10.10.49.87 -w 2
rdma_buf alloc_mw failed
rping_setup_buffers failed: -12
Is ibv_alloc_mw even supported by Mellanox?
EDIT:
I got access to a ConnectX-4 card and got the same error. I can also see that there is an error being logged whenever I try to run rping with the memory window option:
dmesg | tail -n 2
[9349257.246854] mlx4_core 0000:02:00.0: vhcr command 0xd slave:0in_param 0xe26b4000 in_mod=0x110 op_mod=0x0 failed with error:0, status -1
[9349257.246856] mlx4_core 0000:02:00.0: SW2HW_MPT failed (-1)
Upon further exploration it seems this is due to having SR-IOV enabled in the nodes I'm using. Disabling SR-IOV makes this work.