mm/hwpoison: fix refcount of THP head page in no-injection case

Hwpoison injection takes a refcount of target page and another refcount
of head page of THP if the target page is the tail page of a THP.
However, current code doesn't release the refcount of head page if the
THP is not supported to be injected wrt hwpoison filter.

Fix it by reducing the refcount of head page if the target page is the
tail page of a THP and it is not supported to be injected.

Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c
index bf73ac17dad424d9e46857334e5b0befb6805fff..aeba0edd6e447b1e853fdf2eb46547dae363f6f1 100644 (file)
--- a/mm/hwpoison-inject.c
+++ b/mm/hwpoison-inject.c
@@ -58,7 +58,7 @@ inject:
        pr_info("Injecting memory failure at pfn %#lx\n", pfn);
        return memory_failure(pfn, 18, MF_COUNT_INCREASED);
 put_out:
-       put_page(p);
+       put_hwpoison_page(p);
        return 0;
 }