Pull s390 updates from Martin Schwidefsky:
"One performance improvement and a few bug fixes. Two of the fixes
deal with the clock related problems we have seen on recent kernels"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/mm: handle asce-type exceptions as normal page fault
s390,time: revert direct ktime path for s390 clockevent device
s390/time,vdso: convert to the new update_vsyscall interface
s390/uaccess: add missing page table walk range check
s390/mm: optimize copy_page
s390/dasd: validate request size before building CCW/TCW request
s390/signal: always restore saved runtime instrumentation psw bit