diff mbox series

[155/155] include/linux/huge_mm.h: check PageTail in hpage_nr_pages even when !THP

Message ID 20200402041158.dmswX8bQw%akpm@linux-foundation.org (mailing list archive)
State New, archived
Headers show
Series [001/155] tools/accounting/getdelays.c: fix netlink attribute length | expand

Commit Message

Andrew Morton April 2, 2020, 4:11 a.m. UTC 
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: include/linux/huge_mm.h: check PageTail in hpage_nr_pages even when !THP

It's even more important to check that we don't have a tail page when
calling hpage_nr_pages() when THP are disabled.

Link: http://lkml.kernel.org/r/20200318140253.6141-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/huge_mm.h |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
diff mbox series

Patch

--- a/include/linux/huge_mm.h~mm-check-pagetail-in-hpage_nr_pages-even-when-thp
+++ a/include/linux/huge_mm.h
@@ -287,7 +287,11 @@  static inline struct list_head *page_def
 #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; })
 #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; })
 
-#define hpage_nr_pages(x) 1
+static inline int hpage_nr_pages(struct page *page)
+{
+	VM_BUG_ON_PAGE(PageTail(page), page);
+	return 1;
+}
 
 static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
 {