While a faulty cable is used or HCA firmware error, HCA device will be offline. When the driver is accessing this offline device, the following call trace will pop out. " ... [<ffffffff816e4842>] dump_stack+0x63/0x81 [<ffffffff816e459e>] panic+0xcc/0x21b [<ffffffffa03e5f8a>] mlx4_enter_error_state+0xba/0xf0 [mlx4_core] [<ffffffffa03e7298>] mlx4_cmd_reset_flow+0x38/0x60 [mlx4_core] [<ffffffffa03e7381>] mlx4_cmd_poll+0xc1/0x2e0 [mlx4_core] [<ffffffffa03e9f00>] __mlx4_cmd+0xb0/0x160 [mlx4_core] [<ffffffffa0406934>] mlx4_SENSE_PORT+0x54/0xd0 [mlx4_core] [<ffffffffa03f5f54>] mlx4_dev_cap+0x4a4/0xb50 [mlx4_core] ... " In the above call trace, the function mlx4_cmd_poll calls the function mlx4_cmd_post to access the HCA while HCA is offline. Then mlx4_cmd_post returns an error -EIO. Per -EIO, the function mlx4_cmd_poll calls mlx4_cmd_reset_flow to reset HCA. And the above call trace pops out. This is not reasonable. Since HCA device is offline when it is being accessed, it should not be reset again. In this patch, since HCA is offline, the function mlx4_cmd_post returns an error -EINVAL. Per -EINVAL, the function mlx4_cmd_poll directly returns instead of resetting HCA. CC: Srinivas Eeda <srinivas.eeda@xxxxxxxxxx> CC: Junxiao Bi <junxiao.bi@xxxxxxxxxx> Suggested-by: Håkon Bugge <haakon.bugge@xxxxxxxxxx> Signed-off-by: Zhu Yanjun <yanjun.zhu@xxxxxxxxxx> --- drivers/net/ethernet/mellanox/mlx4/cmd.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/net/ethernet/mellanox/mlx4/cmd.c b/drivers/net/ethernet/mellanox/mlx4/cmd.c index 6a9086d..f1c8c42 100644 --- a/drivers/net/ethernet/mellanox/mlx4/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx4/cmd.c @@ -451,6 +451,8 @@ static int mlx4_cmd_post(struct mlx4_dev *dev, u64 in_param, u64 out_param, * Device is going through error recovery * and cannot accept commands. */ + mlx4_err(dev, "%s : Device is in error recovery.\n", __func__); + ret = -EINVAL; goto out; } @@ -657,6 +659,9 @@ static int mlx4_cmd_poll(struct mlx4_dev *dev, u64 in_param, u64 *out_param, } out_reset: + if (err == -EINVAL) + goto out; + if (err) err = mlx4_cmd_reset_flow(dev, op, op_modifier, err); out: @@ -766,6 +771,9 @@ static int mlx4_cmd_wait(struct mlx4_dev *dev, u64 in_param, u64 *out_param, *out_param = context->out_param; out_reset: + if (err == -EINVAL) + goto out; + if (err) err = mlx4_cmd_reset_flow(dev, op, op_modifier, err); out: -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
