On Fri, Aug 31, 2018 at 10:11:24AM +0200, Luc Van Oostenryck wrote:

On Thu, Aug 30, 2018 at 01:41:16PM +0200, Andrey Konovalov wrote:

quoted

This patch adds __force annotations for __user pointers casts detected by
sparse with the -Wcast-from-as flag enabled (added in [1]).

[1] https://github.com/lucvoo/sparse-dev/commit/5f960cb10f56ec2017c128ef9d16060e0145f292

Hi,

It would be nice to have some explanation for why these added __force
are useful.

	It would be even more useful if that series would either deal with
the noise for real ("that's what we intend here, that's what we intend there,
here's a primitive for such-and-such kind of cases, here we actually
ought to pass __user pointer instead of unsigned long", etc.) or left it
unmasked.

	As it is, __force says only one thing: "I know the code is doing
the right thing here".  That belongs in primitives, and I do *not* mean the
#define cast_to_ulong(x) ((__force unsigned long)(x))
kind.

	Folks, if you don't want to deal with that - leave the warnings be.
They do carry more information than "someone has slapped __force in that place".

Al, very annoyed by that kind of information-hiding crap...