net/mlx5: Fix peer devlink set for SF representor devlink port

The cited patch change register devlink flow, and neglect to reflect
the changes for peer devlink set logic. Peer devlink set is
triggering a call trace if done after devl_register.[1]

Hence, align peer devlink set logic with register devlink flow.

[1]
WARNING: CPU: 4 PID: 3394 at net/devlink/core.c:155 devlink_rel_nested_in_add+0x177/0x180
CPU: 4 PID: 3394 Comm: kworker/u40:1 Not tainted 6.9.0-rc4_for_linust_min_debug_2024_04_16_14_08 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Workqueue: mlx5_vhca_event0 mlx5_vhca_state_work_handler [mlx5_core]
RIP: 0010:devlink_rel_nested_in_add+0x177/0x180
Call Trace:
 <TASK>
 ? __warn+0x78/0x120
 ? devlink_rel_nested_in_add+0x177/0x180
 ? report_bug+0x16d/0x180
 ? handle_bug+0x3c/0x60
 ? exc_invalid_op+0x14/0x70
 ? asm_exc_invalid_op+0x16/0x20
 ? devlink_port_init+0x30/0x30
 ? devlink_port_type_clear+0x50/0x50
 ? devlink_rel_nested_in_add+0x177/0x180
 ? devlink_rel_nested_in_add+0xdd/0x180
 mlx5_sf_mdev_event+0x74/0xb0 [mlx5_core]
 notifier_call_chain+0x35/0xb0
 blocking_notifier_call_chain+0x3d/0x60
 mlx5_blocking_notifier_call_chain+0x22/0x30 [mlx5_core]
 mlx5_sf_dev_probe+0x185/0x3e0 [mlx5_core]
 auxiliary_bus_probe+0x38/0x80
 ? driver_sysfs_add+0x51/0x80
 really_probe+0xc5/0x3a0
 ? driver_probe_device+0x90/0x90
 __driver_probe_device+0x80/0x160
 driver_probe_device+0x1e/0x90
 __device_attach_driver+0x7d/0x100
 bus_for_each_drv+0x80/0xd0
 __device_attach+0xbc/0x1f0
 bus_probe_device+0x86/0xa0
 device_add+0x64f/0x860
 __auxiliary_device_add+0x3b/0xa0
 mlx5_sf_dev_add+0x139/0x330 [mlx5_core]
 mlx5_sf_dev_state_change_handler+0x1e4/0x250 [mlx5_core]
 notifier_call_chain+0x35/0xb0
 blocking_notifier_call_chain+0x3d/0x60
 mlx5_vhca_state_work_handler+0x151/0x200 [mlx5_core]
 process_one_work+0x13f/0x2e0
 worker_thread+0x2bd/0x3c0
 ? rescuer_thread+0x410/0x410
 kthread+0xc4/0xf0
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork+0x2d/0x50
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork_asm+0x11/0x20
 </TASK>

Fixes: bf72998 ("net/mlx5: Restore mistakenly dropped parts in register devlink flow")
Fixes: c6e77aa ("net/mlx5: Register devlink first under devlink lock")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240509112951.590184-3-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/mellanox/mlx5/core/main.c

@@ -1680,6 +1680,8 @@ int mlx5_init_one_light(struct mlx5_core_dev *dev)
 	struct devlink *devlink = priv_to_devlink(dev);
 	int err;
 
+	devl_lock(devlink);
+	devl_register(devlink);
 	dev->state = MLX5_DEVICE_STATE_UP;
 	err = mlx5_function_enable(dev, true, mlx5_tout_ms(dev, FW_PRE_INIT_TIMEOUT));
 	if (err) {
@@ -1693,27 +1695,21 @@ int mlx5_init_one_light(struct mlx5_core_dev *dev)
 		goto query_hca_caps_err;
 	}
 
-	devl_lock(devlink);
-	devl_register(devlink);
-
 	err = mlx5_devlink_params_register(priv_to_devlink(dev));
 	if (err) {
 		mlx5_core_warn(dev, "mlx5_devlink_param_reg err = %d\n", err);
-		goto params_reg_err;
+		goto query_hca_caps_err;
 	}
 
 	devl_unlock(devlink);
 	return 0;
 
-params_reg_err:
-	devl_unregister(devlink);
-	devl_unlock(devlink);
 query_hca_caps_err:
-	devl_unregister(devlink);
-	devl_unlock(devlink);
 	mlx5_function_disable(dev, true);
 out:
 	dev->state = MLX5_DEVICE_STATE_INTERNAL_ERROR;
+	devl_unregister(devlink);
+	devl_unlock(devlink);
 	return err;
 }
 

drivers/net/ethernet/mellanox/mlx5/core/sf/dev/driver.c

@@ -60,6 +60,13 @@ static int mlx5_sf_dev_probe(struct auxiliary_device *adev, const struct auxilia
 		goto remap_err;
 	}
 
+	/* Peer devlink logic expects to work on unregistered devlink instance. */
+	err = mlx5_core_peer_devlink_set(sf_dev, devlink);
+	if (err) {
+		mlx5_core_warn(mdev, "mlx5_core_peer_devlink_set err=%d\n", err);
+		goto peer_devlink_set_err;
+	}
+
 	if (MLX5_ESWITCH_MANAGER(sf_dev->parent_mdev))
 		err = mlx5_init_one_light(mdev);
 	else
@@ -69,20 +76,10 @@ static int mlx5_sf_dev_probe(struct auxiliary_device *adev, const struct auxilia
 		goto init_one_err;
 	}
 
-	err = mlx5_core_peer_devlink_set(sf_dev, devlink);
-	if (err) {
-		mlx5_core_warn(mdev, "mlx5_core_peer_devlink_set err=%d\n", err);
-		goto peer_devlink_set_err;
-	}
-
 	return 0;
 
-peer_devlink_set_err:
-	if (mlx5_dev_is_lightweight(sf_dev->mdev))
-		mlx5_uninit_one_light(sf_dev->mdev);
-	else
-		mlx5_uninit_one(sf_dev->mdev);
 init_one_err:
+peer_devlink_set_err:
 	iounmap(mdev->iseg);
 remap_err:
 	mlx5_mdev_uninit(mdev);