Re: What does __user do?

["Robert P. J. Day" <rpjday@xxxxxxxxxxxxxx>]

On Fri, 7 Dec 2007, Peter Poulsen wrote:

> I have noticed __user in some code, when a pointer points to
> userspace code. What does that do exaclty?

it's meant to denote that the pointer is a pointer to *userspace*, not
kernel space.  it doesn't actually get involved in the build process,
it's for sanity checking for "sparse" just to check for consistency
but, from what i remember, it's used fairly erratically throughout the
code.

rday


========================================================================
Robert P. J. Day
Linux Consulting, Training and Annoying Kernel Pedantry
Waterloo, Ontario, CANADA

http://crashcourse.ca
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