6.6-stable review patch. If anyone has any objections, please let me know.
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From: Chenguang Zhao zhaochenguang@kylinos.cn
[ Upstream commit 0e2909c6bec9048f49d0c8e16887c63b50b14647 ]
When cmd_alloc_index(), fails cmd_work_handler() needs to complete ent->slotted before returning early. Otherwise the task which issued the command may hang:
mlx5_core 0000:01:00.0: cmd_work_handler:877:(pid 3880418): failed to allocate command entry INFO: task kworker/13:2:4055883 blocked for more than 120 seconds. Not tainted 4.19.90-25.44.v2101.ky10.aarch64 #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/13:2 D 0 4055883 2 0x00000228 Workqueue: events mlx5e_tx_dim_work [mlx5_core] Call trace: __switch_to+0xe8/0x150 __schedule+0x2a8/0x9b8 schedule+0x2c/0x88 schedule_timeout+0x204/0x478 wait_for_common+0x154/0x250 wait_for_completion+0x28/0x38 cmd_exec+0x7a0/0xa00 [mlx5_core] mlx5_cmd_exec+0x54/0x80 [mlx5_core] mlx5_core_modify_cq+0x6c/0x80 [mlx5_core] mlx5_core_modify_cq_moderation+0xa0/0xb8 [mlx5_core] mlx5e_tx_dim_work+0x54/0x68 [mlx5_core] process_one_work+0x1b0/0x448 worker_thread+0x54/0x468 kthread+0x134/0x138 ret_from_fork+0x10/0x18
Fixes: 485d65e13571 ("net/mlx5: Add a timeout to acquire the command queue semaphore") Signed-off-by: Chenguang Zhao zhaochenguang@kylinos.cn Reviewed-by: Moshe Shemesh moshe@nvidia.com Acked-by: Tariq Toukan tariqt@nvidia.com Link: https://patch.msgid.link/20250108030009.68520-1-zhaochenguang@kylinos.cn Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c index 80af0fc7101f..3e6bd27f6315 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c @@ -1006,6 +1006,7 @@ static void cmd_work_handler(struct work_struct *work) complete(&ent->done); } up(&cmd->vars.sem); + complete(&ent->slotted); return; } } else {