[PATCH 4.14 142/165] s390/mm: fix addressing exception after suspend/resume

From: Greg Kroah-Hartman
Date: Mon Sep 03 2018 - 13:26:56 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx>

commit 37a366face294facb9c9d9fdd9f5b64a27456cbd upstream.

Commit c9b5ad546e7d "s390/mm: tag normal pages vs pages used in page tables"
accidentally changed the logic in arch_set_page_states(), which is used by
the suspend/resume code. set_page_stable(page, order) was changed to
set_page_stable_dat(page, 0). After this, only the first page of higher order
pages will be set to stable, and a write to one of the unstable pages will
result in an addressing exception.

Fix this by using "order" again, instead of "0".

Fixes: c9b5ad546e7d ("s390/mm: tag normal pages vs pages used in page tables")
Cc: stable@xxxxxxxxxxxxxxx # 4.14+
Reviewed-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Signed-off-by: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/s390/mm/page-states.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/s390/mm/page-states.c
+++ b/arch/s390/mm/page-states.c
@@ -271,7 +271,7 @@ void arch_set_page_states(int make_stabl
list_for_each(l, &zone->free_area[order].free_list[t]) {
page = list_entry(l, struct page, lru);
if (make_stable)
- set_page_stable_dat(page, 0);
+ set_page_stable_dat(page, order);
else
set_page_unused(page, order);
}