| Subject | Re: [PATCH 00/18] uaccess: fix sparse warning on get_user for bitwise types | From | Michael Ellerman <> | Date | Mon, 15 Dec 2014 11:40:52 +1100 |
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On Sun, 2014-12-14 at 18:51 +0200, Michael S. Tsirkin wrote: > At the moment, if p and x are both tagged as bitwise types, > get_user(x, p) produces a sparse warning on many architectures. > This is because *p on these architectures is loaded into long > (typically using asm), then cast back to typeof(*p). > > When typeof(*p) is a bitwise type (which is uncommon), such a cast needs > __force, otherwise sparse produces a warning.
What does __force actually mean? Force the cast even though it's a bitfield? Or does it mean more than that?
ie. are we loosing the ability to detect any actual errors by adding force?
cheers
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