Re: [PATCH 04/14] x86/fpu: Remove 'kbuf' parameter from the copy_xstate_to_user() APIs

From: Yu-cheng Yu
Date: Mon Jan 30 2017 - 12:27:06 EST

On Mon, Jan 30, 2017 at 04:45:21PM +0100, Borislav Petkov wrote:
> On Mon, Jan 30, 2017 at 10:57:28AM +0100, Ingo Molnar wrote:
> > Would anyone object to using u32 in these prototypes?
> Well, would there be any disadvantage to forcing them to u32?
> Potentially by something else wanting to use those interfaces besides
> the regset thing and that something else doesn't like u32s?
> Otherwise, I don't see a problem.
> I mean, if 4G are not enough for xstate dimensions then we have a whole
> different problem.

This function pair was intended to be similar to user_regset_copyout(),
user_regset_copyin() used for the standard-format XSAVE area copying.
I totally agree it is complex and should be simplified. Why don't we
do both places?