s390/mm: missing pte for gmap_ipte_notify should trigger a VM_BUG
After fixup_user_fault does not fail we have a writeable pte.
That pte might transform but it should not vanish.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index b1871d3..9c8a6dd 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -752,8 +752,7 @@
break;
/* Walk the process page table, lock and get pte pointer */
ptep = get_locked_pte(gmap->mm, addr, &ptl);
- if (unlikely(!ptep))
- continue;
+ VM_BUG_ON(!ptep);
/* Set notification bit in the pgste of the pte */
entry = *ptep;
if ((pte_val(entry) & (_PAGE_INVALID | _PAGE_PROTECT)) == 0) {