Re: [PATCH net v1] ice: do not reserve resources for RDMA when disabled

[Jesse Brandeburg <jesse.brandeburg@linux.dev>]

On 11/15/24 10:46 AM, Jesse Brandeburg wrote:
> On 11/14/24 10:06 AM, Ertman, David M wrote:
>>>       case ICE_AQC_CAPS_RDMA:
>>> -        caps->rdma = (number == 1);
>>> +        if (IS_ENABLED(CONFIG_INFINIBAND_IRDMA))
>>> +            caps->rdma = (number == 1);
>>>           ice_debug(hw, ICE_DBG_INIT, "%s: rdma = %d\n", prefix,
>>
>> The HW caps struct should always accurately reflect the capabilities 
>> of the HW being probed.  Since this
> 
> why must it accurately reflect the capability of the hardware? The 
> driver state and capability is a reflection of the combination of both, 
> so I'm not sure what the point of your statement.
> 
>> is a kernel configuration (i.e. software) consideration, the more 
>> appropriate approach would be to control
>> the PF flag "ICE_FLAG_RDMA_ENA" based on the kernel CONFIG setting.
> 
> I started making the changes you suggested, but the ICE_FLAG_RDMA_ENA is 
> blindly set by the LAG code, if the cap.rdma is enabled. see 
> ice_set_rdma_cap(). This means the disable won't stick.
> 
> Unless I'm misunderstanding something, ICE_FLAG_RDMA_ENA is used both as 
> a gate and as a state, which is a design issue. This leaves no choice 
> but to implement the way I did in this v1 patch. Do you see any other 
> option to make a simple change that is safe for backporting to stable?

Any comments here Dave?