Hibernation: do not try to mark invalid PFNs as nosave

On some systems some PFNs reported by the early initialization code as
'nosave' may be invalid.  If we try to set the corresponding bits in the
hibernation bitmap, BUG_ON() in memory_bm_find_bit() will be triggered and
the system won't be able to boot (cf.
https://bugzilla.novell.com/show_bug.cgi?id=296242).

Prevent this from happening by verifying if the 'nosave' PFNs are valid in
mark_nosave_pages().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index a3b7854b8f7c..a686590d88c1 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -709,7 +709,8 @@ static void mark_nosave_pages(struct memory_bitmap *bm)
                                 region->end_pfn << PAGE_SHIFT);
 
                 for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++)
-                        memory_bm_set_bit(bm, pfn);
+                        if (pfn_valid(pfn))
+                                memory_bm_set_bit(bm, pfn);
         }
 }