Commit 6972cae5 authored by Dominik Dingel's avatar Dominik Dingel Committed by Martin Schwidefsky
Browse files

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: default avatarDominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 7a5388de

arch/s390/mm/pgtable.c

+1 −2
Original line number Diff line number Diff line
@@ -752,8 +752,7 @@ int gmap_ipte_notify(struct gmap *gmap, unsigned long gaddr, unsigned long len) 
			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) {