diff options
-rw-r--r-- | arch/s390/mm/gmap.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c index c07d64f..4a1434b 100644 --- a/arch/s390/mm/gmap.c +++ b/arch/s390/mm/gmap.c @@ -1455,6 +1455,19 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce, gmap_free(new); return sg; } + if (asce & _ASCE_REAL_SPACE) { + /* only allow one real-space gmap shadow */ + list_for_each_entry(sg, &parent->children, list) { + if (sg->orig_asce & _ASCE_REAL_SPACE) { + spin_lock(&sg->guest_table_lock); + gmap_unshadow(sg); + spin_unlock(&sg->guest_table_lock); + list_del(&sg->list); + gmap_put(sg); + break; + } + } + } atomic_set(&new->ref_count, 2); list_add(&new->list, &parent->children); if (asce & _ASCE_REAL_SPACE) { |