[PATCH AUTOSEL 4.9 13/27] net/mlx5: Fix forced completion access non initialized command entry

From: Sasha Levin
Date: Thu May 14 2020 - 14:56:26 EST


From: Moshe Shemesh <moshe@xxxxxxxxxxxx>

[ Upstream commit f3cb3cebe26ed4c8036adbd9448b372129d3c371 ]

mlx5_cmd_flush() will trigger forced completions to all valid command
entries. Triggered by an asynch event such as fast teardown it can
happen at any stage of the command, including command initialization.
It will trigger forced completion and that can lead to completion on an
uninitialized command entry.

Setting MLX5_CMD_ENT_STATE_PENDING_COMP only after command entry is
initialized will ensure force completion is treated only if command
entry is initialized.

Fixes: 73dd3a4839c1 ("net/mlx5: Avoid using pending command interface slots")
Signed-off-by: Moshe Shemesh <moshe@xxxxxxxxxxxx>
Signed-off-by: Eran Ben Elisha <eranbe@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c
index 1d5263c46eee0..a1057efa2294e 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c
@@ -813,7 +813,6 @@ static void cmd_work_handler(struct work_struct *work)
}

cmd->ent_arr[ent->idx] = ent;
- set_bit(MLX5_CMD_ENT_STATE_PENDING_COMP, &ent->state);
lay = get_inst(cmd, ent->idx);
ent->lay = lay;
memset(lay, 0, sizeof(*lay));
@@ -835,6 +834,7 @@ static void cmd_work_handler(struct work_struct *work)

if (ent->callback)
schedule_delayed_work(&ent->cb_timeout_work, cb_timeout);
+ set_bit(MLX5_CMD_ENT_STATE_PENDING_COMP, &ent->state);

/* Skip sending command to fw if internal error */
if (pci_channel_offline(dev->pdev) ||
--
2.20.1