Re: [PATCH 2/2] crypto: qat - Enforce valid numa configuration.

[Tadeusz Struk <tadeusz.struk@intel.com>]

On 10/08/2014 10:57 AM, Prarit Bhargava wrote:
>>  	node = adf_get_dev_node_id(pdev);
> ^^^ I don't think you should ever make this call.  IMO it is wrong to do it that
> way.  Just stick with
> 
> 	node = dev_to_node(&pdev->dev)
> 
> as the line below forces a default to that anyway.

But then how do I know which node I'm physically connected to?

> 
>> > +	if (node != dev_to_node(&pdev->dev) && dev_to_node(&pdev->dev) > 0) {
>> > +		/* If the accelerator is connected to a node with no memory
>> > +		 * there is no point in using the accelerator since the remote
>> > +		 * memory transaction will be very slow. */
>> > +		dev_err(&pdev->dev, "Invalid NUMA configuration.\n");
>> > +		return -EINVAL;
> Hmm ... I wonder if it would be safe to do
> 
> 	/* force allocations to node 0 */
> 	node = 0;
> 	dev_err(&pdev->dev, "Invalid NUMA configuration detected, node id = %d .
> Defaulting node to 0.  \n",
>                 node);
> 
> and then continue?

As the comment say there is no point continuing if the configuration is
wrong. Defaulting to 0 will cause the same panic you pointed out in your
first patch if node 0 has no memory.

> 
> And maybe even a FW_WARN of some sort here might be appropriate to indicate that
> something is wrong with the mapping?  In any case a better error message is a
> always good idea IMO.