[S390] Protect against sigaltstack wraparound.

This is just a port of 83bd01024b1fdfc41d9b758e5669e80fca72df66
"x86: protect against sigaltstack wraparound".

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2 files changed