[S390] fix list corruption in gmap reverse mapping

This introduces locking via mm->page_table_lock to protect
the rmap list for guest mappings from being corrupted by concurrent
operations.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
1 file changed