[PATCH v2 4/6] mm/page_alloc: clear PageBuddy using __ClearPageBuddy() for bad pages

David Hildenbrand
2024-05-29T11:19:20Z

Let's stop using page_mapcount_reset() and clear PageBuddy using
__ClearPageBuddy() instead.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
mm/page_alloc.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index b1e3eb5787de1..591d28b9f3e48 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -498,7 +498,8 @@ static void bad_page(struct page *page, const char *reason)
dump_stack();
out:
/* Leave bad fields for debug, except PageBuddy could make trouble */
- page_mapcount_reset(page); /* remove PageBuddy */
+ if (PageBuddy(page))
+ __ClearPageBuddy(page);
add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
}

@@ -1346,7 +1347,8 @@ static void check_new_page_bad(struct page *page)
{
if (unlikely(page->flags & __PG_HWPOISON)) {
/* Don't complain about hwpoisoned pages */
- page_mapcount_reset(page); /* remove PageBuddy */
+ if (PageBuddy(page))
+ __ClearPageBuddy(page);
return;
}

--
2.45.1