Re: [PATCH v3 3/8] s390/cio: add basic protected virtualization support

[Michael Mueller <mimu@linux.ibm.com>]

On 03.06.19 15:42, Cornelia Huck wrote:
> On Mon, 3 Jun 2019 14:45:03 +0200
> Michael Mueller <mimu@linux.ibm.com> wrote:
> 
>> On 03.06.19 14:06, Cornelia Huck wrote:
>>> On Wed, 29 May 2019 14:26:52 +0200
>>> Michael Mueller <mimu@linux.ibm.com> wrote:
> 
>>>> @@ -1593,20 +1625,31 @@ struct ccw_device * __init ccw_device_create_console(struct ccw_driver *drv)
>>>>    		return ERR_CAST(sch);
>>>>    
>>>>    	io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
>>>> -	if (!io_priv) {
>>>> -		put_device(&sch->dev);
>>>> -		return ERR_PTR(-ENOMEM);
>>>> -	}
>>>> +	if (!io_priv)
>>>> +		goto err_priv;
>>>> +	io_priv->dma_area = dma_alloc_coherent(&sch->dev,
>>>> +				sizeof(*io_priv->dma_area),
>>>> +				&io_priv->dma_area_dma, GFP_KERNEL);
>>>> +	if (!io_priv->dma_area)
>>>> +		goto err_dma_area;
>>>>    	set_io_private(sch, io_priv);
>>>>    	cdev = io_subchannel_create_ccwdev(sch);
>>>>    	if (IS_ERR(cdev)) {
>>>>    		put_device(&sch->dev);
>>>> +		dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area),
>>>> +				  io_priv->dma_area, io_priv->dma_area_dma);
>>>>    		kfree(io_priv);
>>>
>>> <pre-existing, not introduced by this patch>
>>> Shouldn't that branch do set_io_private(sch, NULL)? Not sure if any
>>> code would make use of it, but it's probably better to clean out
>>> references to freed objects.
>>
>> Added behind kfree(). I hope nobody asks for a separate patch. ;)
> 
> I would probably have added it just before the kfree, but I'm not
> asking for a separate patch ;)

I moved it.

> 
>>
>>> </pre-existing, not introduced by this patch>
>>>    
>>>>    		return cdev;
>>>>    	}
>>>>    	cdev->drv = drv;
>>>>    	ccw_device_set_int_class(cdev);
>>>>    	return cdev;
>>>> +
>>>> +err_dma_area:
>>>> +	kfree(io_priv);
>>>> +err_priv:
>>>> +	put_device(&sch->dev);
>>>> +	return ERR_PTR(-ENOMEM);
>>>>    }
>>>>    
>>>>    void __init ccw_device_destroy_console(struct ccw_device *cdev)
>