net/mlx5: Devcom, only use devcom after NULL check in mlx5_devcom_send_event()

There is a warning reported by kernel test robot:

smatch warnings:
drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c:264
	mlx5_devcom_send_event() warn: variable dereferenced before
		IS_ERR check devcom (see line 259)

The reason for the warning is that the pointer is used before check, put
the assignment to comp after devcom check to silence the warning.

Fixes: 88d162b47981 ("net/mlx5: Devcom, Infrastructure changes")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/r/202308041028.AkXYDwJ6-lkp@intel.com/
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c
index feb62d9526435c7ef804542078e4d579aa87f4ba..00e67910e3ee9d89c17c22ac535ef626e2cdd81f 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c
@@ -256,14 +256,15 @@ int mlx5_devcom_send_event(struct mlx5_devcom_comp_dev *devcom,
                           int event, int rollback_event,
                           void *event_data)
 {
-       struct mlx5_devcom_comp *comp = devcom->comp;
        struct mlx5_devcom_comp_dev *pos;
+       struct mlx5_devcom_comp *comp;
        int err = 0;
        void *data;
 
        if (IS_ERR_OR_NULL(devcom))
                return -ENODEV;
 
+       comp = devcom->comp;
        down_write(&comp->sem);
        list_for_each_entry(pos, &comp->comp_dev_list_head, list) {
                data = rcu_dereference_protected(pos->data, lockdep_is_held(&comp->sem));