linux/drivers/net/netdevsim
Jiri Pirko fc56be47da devlink: convert occ_get op to separate registration
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>
2018-04-08 12:45:57 -04:00
..
Makefile netdevsim: Add simple FIB resource controller via devlink 2018-03-29 14:10:31 -04:00
bpf.c netdevsim: fix overflow on the error path 2018-02-01 11:22:51 +01:00
devlink.c devlink: convert occ_get op to separate registration 2018-04-08 12:45:57 -04:00
fib.c netdevsim: remove incorrect __net_initdata annotations 2018-04-04 12:53:37 -04:00
netdev.c netdevsim: Change nsim_devlink_setup to return error to caller 2018-03-31 22:22:10 -04:00
netdevsim.h netdevsim: Change nsim_devlink_setup to return error to caller 2018-03-31 22:22:10 -04:00