If we can't call page_mapping() to get the page mapping, handle the
anon/ksm/movable bits correctly.
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
mm/debug.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/mm/debug.c b/mm/debug.c
index 4f376514744d..e5de63406b59 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -70,7 +70,12 @@ void __dump_page(struct page *page, const char *reason)
if (page < head || (page >= head + MAX_ORDER_NR_PAGES)) {
/* Corrupt page, cannot call page_mapping */
- mapping = page->mapping;
+ unsigned long tmp = (unsigned long)page->mapping;
+
+ if (tmp & PAGE_MAPPING_ANON)
+ mapping = NULL;
+ else
+ mapping = (void *)(tmp & ~PAGE_MAPPING_FLAGS);
head = page;
compound = false;
} else {
--
2.27.0
