On Wed, Sep 12, 2018 at 05:08:52PM +0200, Arnd Bergmann wrote:
The .ioctl and .compat_ioctl file operations have the same prototype
they can both point to the same function, which works great almost all
the time when all the commands are compatible.
One exception is the s390 architecture, where a compat pointer is only
31 bit wide, and converting it into a 64-bit pointer requires calling
compat_ptr(). Most drivers here will ever run in s390, but since we now
have a generic helper for it, it's easy enough to use it consistently.
I double-checked all these drivers to ensure that all ioctl arguments
are used as pointers or are ignored, but are not interpreted as integer
Signed-off-by: Arnd Bergmann <arnd(a)arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>