提交 a6fc86d2 编写于 作者: P Petr Holasek 提交者: Linus Torvalds

kpagecount: add slab page checking because _mapcount is in a union

Add a PageSlab() check before adding the _mapcount value to /kpagecount.
page->_mapcount is in a union with the SLAB structure so for pages
controlled by SLAB, page_mapcount() returns nonsense.
Signed-off-by: NPetr Holasek <pholasek@redhat.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
上级 c6a34058
......@@ -40,7 +40,7 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
ppage = pfn_to_page(pfn);
else
ppage = NULL;
if (!ppage)
if (!ppage || PageSlab(ppage))
pcount = 0;
else
pcount = page_mapcount(ppage);
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册