queue-4.19/net-mlx5-avoid-reloading-already-removed-devices.patch-5846

   1 From 51e480eb6aba358e6f3f5be906574e3c2b122780 Mon Sep 17 00:00:00 2001
   2 From: Alaa Hleihel <alaa@mellanox.com>
   3 Date: Sun, 19 May 2019 11:11:49 +0300
   4 Subject: net/mlx5: Avoid reloading already removed devices
   5
   6 Prior to reloading a device we must first verify that it was not already
   7 removed. Otherwise, the attempt to remove the device will do nothing, and
   8 in that case we will end up proceeding with adding an new device that no
   9 one was expecting to remove, leaving behind used resources such as EQs that
  10 causes a failure to destroy comp EQs and syndrome (0x30f433).
  11
  12 Fix that by making sure that we try to remove and add a device (based on a
  13 protocol) only if the device is already added.
  14
  15 Fixes: c5447c70594b ("net/mlx5: E-Switch, Reload IB interface when switching devlink modes")
  16 Signed-off-by: Alaa Hleihel <alaa@mellanox.com>
  17 Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
  18 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  19 ---
  20  drivers/net/ethernet/mellanox/mlx5/core/dev.c | 25 +++++++++++++++++--
  21  1 file changed, 23 insertions(+), 2 deletions(-)
  22
  23 diff --git a/drivers/net/ethernet/mellanox/mlx5/core/dev.c b/drivers/net/ethernet/mellanox/mlx5/core/dev.c
  24 index 37ba7c78859d..1c225be9c7db 100644
  25 --- a/drivers/net/ethernet/mellanox/mlx5/core/dev.c
  26 +++ b/drivers/net/ethernet/mellanox/mlx5/core/dev.c
  27 @@ -342,11 +342,32 @@ void mlx5_unregister_interface(struct mlx5_interface *intf)
  28  }
  29  EXPORT_SYMBOL(mlx5_unregister_interface);
  30
  31 +/* Must be called with intf_mutex held */
  32 +static bool mlx5_has_added_dev_by_protocol(struct mlx5_core_dev *mdev, int protocol)
  33 +{
  34 +       struct mlx5_device_context *dev_ctx;
  35 +       struct mlx5_interface *intf;
  36 +       bool found = false;
  37 +
  38 +       list_for_each_entry(intf, &intf_list, list) {
  39 +               if (intf->protocol == protocol) {
  40 +                       dev_ctx = mlx5_get_device(intf, &mdev->priv);
  41 +                       if (dev_ctx && test_bit(MLX5_INTERFACE_ADDED, &dev_ctx->state))
  42 +                               found = true;
  43 +                       break;
  44 +               }
  45 +       }
  46 +
  47 +       return found;
  48 +}
  49 +
  50  void mlx5_reload_interface(struct mlx5_core_dev *mdev, int protocol)
  51  {
  52         mutex_lock(&mlx5_intf_mutex);
  53 -       mlx5_remove_dev_by_protocol(mdev, protocol);
  54 -       mlx5_add_dev_by_protocol(mdev, protocol);
  55 +       if (mlx5_has_added_dev_by_protocol(mdev, protocol)) {
  56 +               mlx5_remove_dev_by_protocol(mdev, protocol);
  57 +               mlx5_add_dev_by_protocol(mdev, protocol);
  58 +       }
  59         mutex_unlock(&mlx5_intf_mutex);
  60  }
  61
  62 --
  63 2.20.1
  64