This resolves race during initialization where the resources with
ops are registered before driver and the structures used by occ_get
op is initialized. So keep occ_get callbacks registered only when
all structs are initialized.
The example flows, as it is in mlxsw:
1) driver load/asic probe:
mlxsw_core
-> mlxsw_sp_resources_register
-> mlxsw_sp_kvdl_resources_register
-> devlink_resource_register IDX
mlxsw_spectrum
-> mlxsw_sp_kvdl_init
-> mlxsw_sp_kvdl_parts_init
-> mlxsw_sp_kvdl_part_init
-> devlink_resource_size_get IDX (to get the current setup
size from devlink)
-> devlink_resource_occ_get_register IDX (register current
occupancy getter)
2) reload triggered by devlink command:
-> mlxsw_devlink_core_bus_device_reload
-> mlxsw_sp_fini
-> mlxsw_sp_kvdl_fini
-> devlink_resource_occ_get_unregister IDX
(struct mlxsw_sp *mlxsw_sp is freed at this point, call to occ get
which is using mlxsw_sp would cause use-after free)
-> mlxsw_sp_init
-> mlxsw_sp_kvdl_init
-> mlxsw_sp_kvdl_parts_init
-> mlxsw_sp_kvdl_part_init
-> devlink_resource_size_get IDX (to get the current setup
size from devlink)
-> devlink_resource_occ_get_register IDX (register current
occupancy getter)
Fixes: d9f9b9a4d0 ("devlink: Add support for resource abstraction")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fc56be47da