[PATCH v2 8/8] PM / Hibernate: exclude all PageOffline() pages

From: David Hildenbrand
Date: Thu Nov 22 2018 - 05:07:33 EST


The content of pages that are marked PG_offline is not of interest
(e.g. inflated by a balloon driver), let's skip these pages.

In saveable_highmem_page(), move the PageReserved() check to a new
check along with the PageOffline() check to separate it from the
swsusp checks.

Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: Pavel Machek <pavel@xxxxxx>
Cc: Len Brown <len.brown@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
Acked-by: Pavel Machek <pavel@xxxxxx>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
---
kernel/power/snapshot.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 87e6dd57819f..4802b039b89f 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1221,8 +1221,10 @@ static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn)

BUG_ON(!PageHighMem(page));

- if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page) ||
- PageReserved(page))
+ if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page))
+ return NULL;
+
+ if (PageReserved(page) || PageOffline(page))
return NULL;

if (page_is_guard(page))
@@ -1286,6 +1288,9 @@ static struct page *saveable_page(struct zone *zone, unsigned long pfn)
if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page))
return NULL;

+ if (PageOffline(page))
+ return NULL;
+
if (PageReserved(page)
&& (!kernel_page_present(page) || pfn_is_nosave(pfn)))
return NULL;
--
2.17.2