On Fri, Aug 11, 2023 at 05:36:05PM +0100, Catalin Marinas wrote:

On Mon, Aug 07, 2023 at 11:00:12PM +0100, Mark Brown wrote:

quoted

+static inline int copy_to_user_gcs(unsigned long __user *addr,
+				   unsigned long *val,
+				   int count)

I think it makes more sense to have a put_user_gcs() of a single
element. I've only seen it used with 2 elements in the signal code but
we could as well do two put_user_gcs() calls (as we do for other stuff
that we push to the signal frame).

Right, it's just the two element array in the signals code and the one
element for the context token in map_shadow_stack().  I can refactor to
a single read/write operation, I'd originally written it that way but I
wasn't thrilled with either writing a load of fun macros to mirror the
way vanilla put_user() is written or having code that looked very
different to the other similarly named functions were done.