Refactor it to use s390_get_feat_block(). Directly write into the mapped
lowcore with stfl and make sure it is really only compiled if needed.
While at it, add an alignment check for STFLE and avoid
potential_page_fault() by properly restoring the CPU state.
Due to s390_get_feat_block(), we will now also indicate the
"Configuration-z-architectural-mode", which is with new SIGP code the
right thing to do.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-30-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
f74990a5d0