[PATCH] forced argument Was Re: sparse: incorrect type in argument1 (different address spaces)

[Christopher Li]

This is a multi-part message in MIME format.On 04/22/2013 11:16 PM, Dan Carpenter wrote:
> That didn't work.  It's the the void * in the parameter list that's
> the problem.  We'd need to do something like the patch below:
> 
> Otherwise we could add "__ok_to_cast" thing to Sparse maybe?

Thanks for the insight. I make a small patch to test the __ok_to_cast
feature. The syntax is adding the force attribute to the argument
declaration.

it will look like this:
static inline long __must_check PTR_ERR( __force const void *ptr)

That means the "ptr" argument will perform a forced cast when receiving
the argument. It is OK to pass __iomem pointer to "ptr".

The example are in the patch. It need to patch both sparse and the
Linux tree.

What do you say?

Chris