From: Moshe Shemesh moshe@nvidia.com
[ Upstream commit 8e715cd613a1e872b9d918e912d90b399785761a ]
Avoid a race where command work handler may fail to allocate command entry index, by holding the command semaphore down till command entry index is being freed.
Fixes: 410bd754cd73 ("net/mlx5: Add retry mechanism to the command entry index allocation") Signed-off-by: Moshe Shemesh moshe@nvidia.com Reviewed-by: Eran Ben Elisha eranbe@nvidia.com Signed-off-by: Saeed Mahameed saeedm@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c index 2e55e00888715..20e3f8cd074a1 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c @@ -147,8 +147,12 @@ static void cmd_ent_put(struct mlx5_cmd_work_ent *ent) if (!refcount_dec_and_test(&ent->refcnt)) return;
- if (ent->idx >= 0) - cmd_free_index(ent->cmd, ent->idx); + if (ent->idx >= 0) { + struct mlx5_cmd *cmd = ent->cmd; + + cmd_free_index(cmd, ent->idx); + up(ent->page_queue ? &cmd->pages_sem : &cmd->sem); + }
cmd_free_ent(ent); } @@ -1582,8 +1586,6 @@ static void mlx5_cmd_comp_handler(struct mlx5_core_dev *dev, u64 vec, bool force vector = vec & 0xffffffff; for (i = 0; i < (1 << cmd->log_sz); i++) { if (test_bit(i, &vector)) { - struct semaphore *sem; - ent = cmd->ent_arr[i];
/* if we already completed the command, ignore it */ @@ -1606,10 +1608,6 @@ static void mlx5_cmd_comp_handler(struct mlx5_core_dev *dev, u64 vec, bool force dev->state == MLX5_DEVICE_STATE_INTERNAL_ERROR) cmd_ent_put(ent);
- if (ent->page_queue) - sem = &cmd->pages_sem; - else - sem = &cmd->sem; ent->ts2 = ktime_get_ns(); memcpy(ent->out->first.data, ent->lay->out, sizeof(ent->lay->out)); dump_command(dev, ent, 0); @@ -1663,7 +1661,6 @@ static void mlx5_cmd_comp_handler(struct mlx5_core_dev *dev, u64 vec, bool force */ complete(&ent->done); } - up(sem); } } }