1) ptrace should pass 'current' to task_user_regset_view()
2) When fetching general registers using a 64-bit view, and
the target is 32-bit, we have to convert.
3) Skip the whole register window get/set code block if
the user isn't asking to access anything in there.
Otherwise we have problems if the user doesn't have
an address space setup. Fetching ptrace register is
still valid at such a time, and ptrace does not try
to access the register window area of the regset.
Signed-off-by: David S. Miller <davem@davemloft.net>
d786a4a659