From: Vadim Pasternak <vadimp@nvidia.com>

Drop devl_lock() / devl_unlock() from ports creation and removal flows
since the devlink instance lock is now taken by mlxsw_core.

Fixes: 72a4c8c94efa ("mlxsw: convert driver to use unlocked devlink API during init/fini")
Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlxsw/minimal.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/minimal.c b/drivers/net/ethernet/mellanox/mlxsw/minimal.c
index d9bf584234a6..bb1cd4bae82e 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/minimal.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/minimal.c
@@ -328,7 +328,6 @@ static void mlxsw_m_port_module_unmap(struct mlxsw_m *mlxsw_m, u8 module)
 static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
 {
 	unsigned int max_ports = mlxsw_core_max_ports(mlxsw_m->core);
-	struct devlink *devlink = priv_to_devlink(mlxsw_m->core);
 	u8 last_module = max_ports;
 	int i;
 	int err;
@@ -357,7 +356,6 @@ static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
 	}
 
 	/* Create port objects for each valid entry */
-	devl_lock(devlink);
 	for (i = 0; i < mlxsw_m->max_ports; i++) {
 		if (mlxsw_m->module_to_port[i] > 0) {
 			err = mlxsw_m_port_create(mlxsw_m,
@@ -367,7 +365,6 @@ static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
 				goto err_module_to_port_create;
 		}
 	}
-	devl_unlock(devlink);
 
 	return 0;
 
@@ -377,7 +374,6 @@ static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
 			mlxsw_m_port_remove(mlxsw_m,
 					    mlxsw_m->module_to_port[i]);
 	}
-	devl_unlock(devlink);
 	i = max_ports;
 err_module_to_port_map:
 	for (i--; i > 0; i--)
@@ -390,10 +386,8 @@ static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
 
 static void mlxsw_m_ports_remove(struct mlxsw_m *mlxsw_m)
 {
-	struct devlink *devlink = priv_to_devlink(mlxsw_m->core);
 	int i;
 
-	devl_lock(devlink);
 	for (i = 0; i < mlxsw_m->max_ports; i++) {
 		if (mlxsw_m->module_to_port[i] > 0) {
 			mlxsw_m_port_remove(mlxsw_m,
@@ -401,7 +395,6 @@ static void mlxsw_m_ports_remove(struct mlxsw_m *mlxsw_m)
 			mlxsw_m_port_module_unmap(mlxsw_m, i);
 		}
 	}
-	devl_unlock(devlink);
 
 	kfree(mlxsw_m->module_to_port);
 	kfree(mlxsw_m->ports);
-- 
2.35.3

Hello:

This patch was applied to netdev/net.git (master)
by Jakub Kicinski <kuba@kernel.org>:

On Thu, 11 Aug 2022 11:57:36 +0200 you wrote:
> From: Vadim Pasternak <vadimp@nvidia.com>
> 
> Drop devl_lock() / devl_unlock() from ports creation and removal flows
> since the devlink instance lock is now taken by mlxsw_core.
> 
> Fixes: 72a4c8c94efa ("mlxsw: convert driver to use unlocked devlink API during init/fini")
> Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
> Signed-off-by: Ido Schimmel <idosch@nvidia.com>
> Signed-off-by: Petr Machata <petrm@nvidia.com>
> 
> [...]

Here is the summary with links:
  - [net] mlxsw: minimal: Fix deadlock in ports creation
    https://git.kernel.org/netdev/net/c/4f98cb0408b0

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

CC'ing Jiri, which I forgot to do.

Petr Machata <petrm@nvidia.com> writes:

> From: Vadim Pasternak <vadimp@nvidia.com>
>
> Drop devl_lock() / devl_unlock() from ports creation and removal flows
> since the devlink instance lock is now taken by mlxsw_core.
>
> Fixes: 72a4c8c94efa ("mlxsw: convert driver to use unlocked devlink API during init/fini")
> Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
> Signed-off-by: Ido Schimmel <idosch@nvidia.com>
> Signed-off-by: Petr Machata <petrm@nvidia.com>
> ---
>  drivers/net/ethernet/mellanox/mlxsw/minimal.c | 7 -------
>  1 file changed, 7 deletions(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlxsw/minimal.c b/drivers/net/ethernet/mellanox/mlxsw/minimal.c
> index d9bf584234a6..bb1cd4bae82e 100644
> --- a/drivers/net/ethernet/mellanox/mlxsw/minimal.c
> +++ b/drivers/net/ethernet/mellanox/mlxsw/minimal.c
> @@ -328,7 +328,6 @@ static void mlxsw_m_port_module_unmap(struct mlxsw_m *mlxsw_m, u8 module)
>  static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
>  {
>  	unsigned int max_ports = mlxsw_core_max_ports(mlxsw_m->core);
> -	struct devlink *devlink = priv_to_devlink(mlxsw_m->core);
>  	u8 last_module = max_ports;
>  	int i;
>  	int err;
> @@ -357,7 +356,6 @@ static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
>  	}
>  
>  	/* Create port objects for each valid entry */
> -	devl_lock(devlink);
>  	for (i = 0; i < mlxsw_m->max_ports; i++) {
>  		if (mlxsw_m->module_to_port[i] > 0) {
>  			err = mlxsw_m_port_create(mlxsw_m,
> @@ -367,7 +365,6 @@ static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
>  				goto err_module_to_port_create;
>  		}
>  	}
> -	devl_unlock(devlink);
>  
>  	return 0;
>  
> @@ -377,7 +374,6 @@ static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
>  			mlxsw_m_port_remove(mlxsw_m,
>  					    mlxsw_m->module_to_port[i]);
>  	}
> -	devl_unlock(devlink);
>  	i = max_ports;
>  err_module_to_port_map:
>  	for (i--; i > 0; i--)
> @@ -390,10 +386,8 @@ static int mlxsw_m_ports_create(struct mlxsw_m *mlxsw_m)
>  
>  static void mlxsw_m_ports_remove(struct mlxsw_m *mlxsw_m)
>  {
> -	struct devlink *devlink = priv_to_devlink(mlxsw_m->core);
>  	int i;
>  
> -	devl_lock(devlink);
>  	for (i = 0; i < mlxsw_m->max_ports; i++) {
>  		if (mlxsw_m->module_to_port[i] > 0) {
>  			mlxsw_m_port_remove(mlxsw_m,
> @@ -401,7 +395,6 @@ static void mlxsw_m_ports_remove(struct mlxsw_m *mlxsw_m)
>  			mlxsw_m_port_module_unmap(mlxsw_m, i);
>  		}
>  	}
> -	devl_unlock(devlink);
>  
>  	kfree(mlxsw_m->module_to_port);
>  	kfree(mlxsw_m->ports);

Thu, Aug 11, 2022 at 01:44:17PM CEST, petrm@nvidia.com wrote:
>CC'ing Jiri, which I forgot to do.

Oups, I forgot the minimal driver. Sorry about that.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>