Timo Rothenpieler timo@rothenpieler.org 于2020年11月18日周三 下午7:28写道：

Hi,

After 50b2412b7e7862c5af0cbf4b10d93bc5c712d021 was backported to stable branches (I only tested 5.4), some serious issues started to arrise.

According to linux-rdma, the following two patches that need to go along with 50b2412b7e are missing:

...

1. 1d5558b1f0de net/mlx5: poll cmd EQ in case of command timeout
2. 410bd754cd73 net/mlx5: Add retry mechanism to the command entry ...

I managed to apply those mostly cleanly after also applying two dependencies. So the complete list of needed commits for 5.4 is:

1. 3ed879965cc4 net/mlx5: Use async EQ setup cleanup helpers ...
2. 1d5558b1f0de net/mlx5: poll cmd EQ in case of command timeout
3. d43b7007dbd1 net/mlx5: Fix a race when moving command ...
4. 410bd754cd73 net/mlx5: Add retry mechanism to the command entry ...

With those 4 commits applied, the issue is fixed. For reference, that's the output I get with 5.4.77:

...

Nov 17 01:12:58 store01 kernel: mlx5_ib: Mellanox Connect-IB Infiniband driver v5.0-0 Nov 17 01:12:58 store01 kernel: mlx5_core 0000:01:00.0: cmd_work_handler:887:(pid 383): failed to allocate command entry Nov 17 01:12:58 store01 kernel: infiniband mlx5_0: reg_mr_callback:104:(pid 383): async reg mr failed. status -11 Nov 17 01:12:58 store01 kernel: mlx5_core 0000:01:00.0: cmd_work_handler:887:(pid 383): failed to allocate command entry Nov 17 01:12:58 store01 kernel: mlx5_core 0000:01:00.0: mlx5e_create_mdev_resources:104:(pid 1): alloc td failed, -11 Nov 17 01:12:58 store01 kernel: mlx5_0, 1: ipoib_intf_alloc failed -11

+cc Greg & Sascha Hi,

We hit the same problem on mlx5, I've tested four mentioned commits, it works fine, please include them in future 5.4 kernel.

Thanks! Jack Wang

On Wed, Nov 18, 2020 at 07:28:30PM +0100, Timo Rothenpieler wrote:

Hi,

After 50b2412b7e7862c5af0cbf4b10d93bc5c712d021 was backported to stable branches (I only tested 5.4), some serious issues started to arrise.

According to linux-rdma, the following two patches that need to go along with 50b2412b7e are missing:

...

1. 1d5558b1f0de net/mlx5: poll cmd EQ in case of command timeout
2. 410bd754cd73 net/mlx5: Add retry mechanism to the command entry ...

I managed to apply those mostly cleanly after also applying two dependencies. So the complete list of needed commits for 5.4 is:

1. 3ed879965cc4 net/mlx5: Use async EQ setup cleanup helpers ...
2. 1d5558b1f0de net/mlx5: poll cmd EQ in case of command timeout
3. d43b7007dbd1 net/mlx5: Fix a race when moving command ...
4. 410bd754cd73 net/mlx5: Add retry mechanism to the command entry ...

With those 4 commits applied, the issue is fixed. For reference, that's the output I get with 5.4.77:

All now queued up, thanks.

greg k-h