From: Wei Yang <richardw.yang@linux.intel.com>
Date: Fri, 31 Jan 2020 06:14:29 +0000 (-0800)
Subject: mm/huge_memory.c: use head to check huge zero page
X-Git-Tag: v5.6-rc1~100^2~56
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=cb829624867b5ab10bc6a7036d183b1b82bfe9f8;p=users%2Fhch%2Fblock.git

mm/huge_memory.c: use head to check huge zero page

The page could be a tail page, if this is the case, this BUG_ON will
never be triggered.

Link: http://lkml.kernel.org/r/20200110032610.26499-1-richardw.yang@linux.intel.com
Fixes: e9b61f19858a ("thp: reintroduce split_huge_page()")

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index a88093213674..ee1dafedd8fe 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2712,7 +2712,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 	unsigned long flags;
 	pgoff_t end;
 
-	VM_BUG_ON_PAGE(is_huge_zero_page(page), page);
+	VM_BUG_ON_PAGE(is_huge_zero_page(head), head);
 	VM_BUG_ON_PAGE(!PageLocked(page), page);
 	VM_BUG_ON_PAGE(!PageCompound(page), page);