[PATCH 7/8] mm: Always check PagePolicyNoCompound

[Matthew Wilcox <willy@infradead.org>]

From: Matthew Wilcox <mawilcox@microsoft.com>

Currently, we're only checking that a page is not compound when we're
setting or clearing a bit.  We should probably be checking the page
isn't compound when testing the bit too.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
---
 include/linux/page-flags.h | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index ac55f6c94c0a..1960b5e4b9ab 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -178,11 +178,10 @@ struct page *PagePolicyTailRead(struct page *page, bool modify)
 	return compound_head(page);
 }
 
-static __always_inline
-struct page *PagePolicyNoCompound(struct page *page, bool modify)
+static __always_inline struct page *PagePolicyNoCompound(struct page *page)
 {
 	CheckPageInit(page);
-	VM_BUG_ON_PGFLAGS(modify && PageCompound(page), page);
+	VM_BUG_ON_PGFLAGS(PageCompound(page), page);
 	return page;
 }
 
@@ -212,7 +211,7 @@ struct page *PagePolicyNoCompound(struct page *page, bool modify)
 #define PF_HEAD(page, modify)		compound_head(CheckPageInit(page))
 #define PF_ONLY_HEAD(page, modify)	PagePolicyOnlyHead(page)
 #define PF_TAIL_READ(page, modify)	PagePolicyTailRead(page, modify)
-#define PF_NO_COMPOUND(page, modify)	PagePolicyNoCompound(page, modify)
+#define PF_NO_COMPOUND(page, modify)	PagePolicyNoCompound(page)
 
 /*
  * Macros to create function definitions for page flags
-- 
2.16.3