Mellanox plugin should handle Bluefield card in DPU mode correctly

[ykulazhenkov]

Mellanox plugin should handle Bluefield card in DPU mode correctly

Currently, the Mellanox plugin will try to change the FW configuration for the card and reboot the node.
Changing the FW configuration for BF in DPU mode requires a power cycle of the entire host.
The operator can't handle this correctly, which leads to an infinite reboot loop.

Proposed behavior:

• The Mellanox plugin should fail if it detects that the FW configuration of the BF in DPU mode doesn't match the policy configuration (the operator will not proceed with the configuration)
• The Mellanox plugin should skip the FW configuration reset for BF in DPU mode.

Alternative 1:

• The Mellanox plugin should apply the configuration to the DPU's FW, print a SCARY WARNING to the log, and emit an event that a manual power cycle is required to break a reboot loop.

Alternative 2:

• The Mellanox plugin should print a warning message if it detects that the DPU's FW config doesn't match the policy and then ignore the device.
• The generic plugin should be modified to ignore BF devices in DPU mode if they have an invalid FW config.

I personally prefer the option from the "Proposed behavior" section.

@e0ne @SchSeba @zeeke Please, share your thoughts

[adrianchiris]

+1 for the Proposed behavior

hopefully for DPU we will be able to load configuration by mstfwreset+reboot and save the powercycle
then we can remove this check from the mellanox plugin