Re: mlx5_core 5.10 stable series regression starting at 5.10.65

On Mon, Sep 20, 2021 at 08:22:44PM +0000, Patrick.Mclean@sony.com wrote:

In 5.10 stable kernels since 5.10.65 certain mlx5 cards are no longer usable (relevant dmesg logs and lspci output are pasted below).

Bisecting the problem tracks the problem down to this commit:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.10.y&id=fe6322774ca28669868a7e231e173e09f7422118

Here is how lscpi -nn identifies the cards:
41:00.0 Ethernet controller [0200]: Mellanox Technologies MT27800 Family [ConnectX-5] [15b3:1017]
41:00.1 Ethernet controller [0200]: Mellanox Technologies MT27800 Family [ConnectX-5] [15b3:1017]

Here are the relevant dmesg logs:
[   13.409473] mlx5_core 0000:41:00.0: firmware version: 16.31.1014
[   13.415944] mlx5_core 0000:41:00.0: 126.016 Gb/s available PCIe bandwidth (8.0 GT/s PCIe x16 link)
[   13.707425] mlx5_core 0000:41:00.0: Rate limit: 127 rates are supported, range: 0Mbps to 24414Mbps
[   13.718221] mlx5_core 0000:41:00.0: E-Switch: Total vports 2, per vport: max uc(128) max mc(2048)
[   13.740607] mlx5_core 0000:41:00.0: Port module event: module 0, Cable plugged
[   13.759857] mlx5_core 0000:41:00.0: mlx5_pcie_event:294:(pid 586): PCIe slot advertised sufficient power (75W).
[   17.986973] mlx5_core 0000:41:00.0: E-Switch: cleanup
[   18.686204] mlx5_core 0000:41:00.0: init_one:1371:(pid 803): mlx5_load_one failed with error code -22
[   18.701352] mlx5_core: probe of 0000:41:00.0 failed with error -22
[   18.727364] mlx5_core 0000:41:00.1: firmware version: 16.31.1014
[   18.743853] mlx5_core 0000:41:00.1: 126.016 Gb/s available PCIe bandwidth (8.0 GT/s PCIe x16 link)
[   19.015349] mlx5_core 0000:41:00.1: Rate limit: 127 rates are supported, range: 0Mbps to 24414Mbps
[   19.025157] mlx5_core 0000:41:00.1: E-Switch: Total vports 2, per vport: max uc(128) max mc(2048)
[   19.053569] mlx5_core 0000:41:00.1: Port module event: module 1, Cable unplugged
[   19.062093] mlx5_core 0000:41:00.1: mlx5_pcie_event:294:(pid 591): PCIe slot advertised sufficient power (75W).
[   22.826932] mlx5_core 0000:41:00.1: E-Switch: cleanup
[   23.544747] mlx5_core 0000:41:00.1: init_one:1371:(pid 803): mlx5_load_one failed with error code -22
[   23.555071] mlx5_core: probe of 0000:41:00.1 failed with error -22

Please let me know if I can provide any further information.

If you revert that single change, do things work properly?

Does newer kernels (5.14, 5.15-rc2) work properly for you as well?

thanks,

greg k-h