On Mon, Aug 26, 2013 at 04:46:13PM +0800, Wanpeng Li wrote:
>Hwpoison inject doesn't implement read method for corrupt-pfn/unpoison-pfn
>attributes:
>
># cat /sys/kernel/debug/hwpoison/corrupt-pfn 
>cat: /sys/kernel/debug/hwpoison/corrupt-pfn: Permission denied
># cat /sys/kernel/debug/hwpoison/unpoison-pfn 
>cat: /sys/kernel/debug/hwpoison/unpoison-pfn: Permission denied
>
>This patch change the permission of corrupt-pfn/unpoison-pfn to 0400.
>
>Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
>---
> mm/hwpoison-inject.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
>diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c
>index 3a61efc..8b77bfd 100644
>--- a/mm/hwpoison-inject.c
>+++ b/mm/hwpoison-inject.c
>@@ -88,12 +88,12 @@ static int pfn_inject_init(void)
> 	 * hardware status change, hence do not require hardware support.
> 	 * They are mainly for testing hwpoison in software level.
> 	 */
>-	dentry = debugfs_create_file("corrupt-pfn", 0600, hwpoison_dir,
>+	dentry = debugfs_create_file("corrupt-pfn", 0400, hwpoison_dir,
> 					  NULL, &hwpoison_fops);
> 	if (!dentry)
> 		goto fail;
>
>-	dentry = debugfs_create_file("unpoison-pfn", 0600, hwpoison_dir,
>+	dentry = debugfs_create_file("unpoison-pfn", 0400, hwpoison_dir,
> 				     NULL, &unpoison_fops);
> 	if (!dentry)
> 		goto fail;
>-- 
>1.8.1.2

Fix this patch: