Received-SPF: pass (google.com: domain of linux-kernel+bounces-194008-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
From: David Hildenbrand <david@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org,
	David Hildenbrand <david@redhat.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	"Matthew Wilcox (Oracle)" <willy@infradead.org>,
	Mike Rapoport <rppt@kernel.org>,
	Minchan Kim <minchan@kernel.org>,
	Sergey Senozhatsky <senozhatsky@chromium.org>,
	Hyeonggon Yoo <42.hyeyoo@gmail.com>
Subject: [PATCH v2 4/6] mm/page_alloc: clear PageBuddy using __ClearPageBuddy() for bad pages
Date: Wed, 29 May 2024 13:19:02 +0200
Message-ID: <20240529111904.2069608-5-david@redhat.com>
In-Reply-To: <20240529111904.2069608-1-david@redhat.com>
References: <20240529111904.2069608-1-david@redhat.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

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