Re: [PATCH v3 1/2] xen/xenbus: reference count registered modules

[Jan Beulich]

On 02.12.2019 12:41, Paul Durrant wrote:
> To prevent a PV driver module being removed whilst attached to its other
> end, and hence xenbus calling into potentially invalid text, take a
> reference on the module before calling the probe() method (dropping it if
> unsuccessful) and drop the reference after returning from the remove()
> method.
> 
> Suggested-by: Jan Beulich <jbeulich@xxxxxxxx>
> Signed-off-by: Paul Durrant <pdurrant@xxxxxxxxxx>

Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
with ...

> --- a/drivers/xen/xenbus/xenbus_probe.c
> +++ b/drivers/xen/xenbus/xenbus_probe.c
> @@ -232,9 +232,16 @@ int xenbus_dev_probe(struct device *_dev)
>  		return err;
>  	}
>  
> +	if (!try_module_get(drv->driver.owner)) {
> +		dev_warn(&dev->dev, "failed to acquire module reference on '%s'.\n",
> +			 drv->driver.name);

... perhaps the full stop dropped here and ...

> +		err = -ESRCH;
> +		goto fail;
> +        }

... (definitely) indentation here changed to use a tab.

Jan