Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

[linux-2.6-microblaze.git] / net / core / page_pool.c

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index ac11604..e140905 100644 (file)
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -739,7 +739,15 @@ bool page_pool_return_skb_page(struct page *page)
        struct page_pool *pp;
 
        page = compound_head(page);
-       if (unlikely(page->pp_magic != PP_SIGNATURE))
+
+       /* page->pp_magic is OR'ed with PP_SIGNATURE after the allocation
+        * in order to preserve any existing bits, such as bit 0 for the
+        * head page of compound page and bit 1 for pfmemalloc page, so
+        * mask those bits for freeing side when doing below checking,
+        * and page_is_pfmemalloc() is checked in __page_pool_put_page()
+        * to avoid recycling the pfmemalloc page.
+        */
+       if (unlikely((page->pp_magic & ~0x3UL) != PP_SIGNATURE))
                return false;
 
        pp = page->pp;