s390/mm: downgrade page table after fork of a 31 bit process

[cascardo/linux.git] / arch / s390 / mm / mmap.c

diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
index 5733842..c59a5ef 100644 (file)
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -103,9 +103,15 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
 
 int s390_mmap_check(unsigned long addr, unsigned long len)
 {
+       int rc;
+
        if (!is_compat_task() &&
-           len >= TASK_SIZE && TASK_SIZE < (1UL << 53))
-               return crst_table_upgrade(current->mm, 1UL << 53);
+           len >= TASK_SIZE && TASK_SIZE < (1UL << 53)) {
+               rc = crst_table_upgrade(current->mm, 1UL << 53);
+               if (rc)
+                       return rc;
+               update_mm(current->mm, current);
+       }
        return 0;
 }
 
@@ -125,6 +131,7 @@ s390_get_unmapped_area(struct file *filp, unsigned long addr,
                rc = crst_table_upgrade(mm, 1UL << 53);
                if (rc)
                        return (unsigned long) rc;
+               update_mm(mm, current);
                area = arch_get_unmapped_area(filp, addr, len, pgoff, flags);
        }
        return area;
@@ -147,6 +154,7 @@ s390_get_unmapped_area_topdown(struct file *filp, const unsigned long addr,
                rc = crst_table_upgrade(mm, 1UL << 53);
                if (rc)
                        return (unsigned long) rc;
+               update_mm(mm, current);
                area = arch_get_unmapped_area_topdown(filp, addr, len,
                                                      pgoff, flags);
        }