Re: [PATCH repost 12/16] parisc/uaccess: fix sparse errors
From: James Bottomley
Date: Wed Dec 31 2014 - 15:23:42 EST
On Wed, 2014-12-31 at 20:38 +0200, Michael S. Tsirkin wrote:
> On Wed, Dec 31, 2014 at 09:17:20AM -0800, James Bottomley wrote:
> > OK, parisc developers still being dense, but this does look like an
> > abuse of the bitwise type.
> To give you another example:
> __le16 __user *p;
> __le16 foo;
> int rc = get_user(v, p);
> really should be fine, ATM this gives a warning.
OK, I think I've figured it out. You're saying that casting __gu_val to
a bitwise annotated type is an automatic sparse failure because it has
to be a long in our assembly code to receive the load/store as a
register. However, this is required for sparse to do the correct lvalue
type = rvalue type check in the assignment to x. We were all thinking
the __force just killed these sparse type checks.
In that case, I think parisc is fine with this.
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