3 files changed, 106 insertions, 5 deletions
diff --git a/Documentation/ABI/testing/sysfs-memory-page-offline b/Documentation/ABI/testing/sysfs-memory-page-offline
new file mode 100644
index 000000000000..e14703f12fdf
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-memory-page-offline
@@ -0,0 +1,44 @@
+What:		/sys/devices/system/memory/soft_offline_page
+Date:		Sep 2009
+KernelVersion:	2.6.33
+Contact:	andi@firstfloor.org
+Description:
+		Soft-offline the memory page containing the physical address
+		written into this file. Input is a hex number specifying the
+		physical address of the page. The kernel will then attempt
+		to soft-offline it, by moving the contents elsewhere or
+		dropping it if possible. The kernel will then be placed
+		on the bad page list and never be reused.
+
+		The offlining is done in kernel specific granuality.
+		Normally it's the base page size of the kernel, but
+		this might change.
+
+		The page must be still accessible, not poisoned. The
+		kernel will never kill anything for this, but rather
+		fail the offline.  Return value is the size of the
+		number, or a error when the offlining failed.  Reading
+		the file is not allowed.
+
+What:		/sys/devices/system/memory/hard_offline_page
+Date:		Sep 2009
+KernelVersion:	2.6.33
+Contact:	andi@firstfloor.org
+Description:
+		Hard-offline the memory page containing the physical
+		address written into this file. Input is a hex number
+		specifying the physical address of the page. The
+		kernel will then attempt to hard-offline the page, by
+		trying to drop the page or killing any owner or
+		triggering IO errors if needed.  Note this may kill
+		any processes owning the page. The kernel will avoid
+		to access this page assuming it's poisoned by the
+		hardware.
+
+		The offlining is done in kernel specific granuality.
+		Normally it's the base page size of the kernel, but
+		this might change.
+
+		Return value is the size of the number, or a error when
+		the offlining failed.
+		Reading the file is not allowed.
diff --git a/Documentation/vm/hwpoison.txt b/Documentation/vm/hwpoison.txt
index 3ffadf8da61f..12f9ba20ccb7 100644
--- a/Documentation/vm/hwpoison.txt
+++ b/Documentation/vm/hwpoison.txt
@@ -92,16 +92,62 @@ PR_MCE_KILL_GET
 
 Testing:
 
-madvise(MADV_POISON, ....)
+madvise(MADV_HWPOISON, ....)
 	(as root)
 	Poison a page in the process for testing
 
 
 hwpoison-inject module through debugfs
-	/sys/debug/hwpoison/corrupt-pfn
 
-Inject hwpoison fault at PFN echoed into this file
+/sys/debug/hwpoison/
 
+corrupt-pfn
+
+Inject hwpoison fault at PFN echoed into this file. This does
+some early filtering to avoid corrupted unintended pages in test suites.
+
+unpoison-pfn
+
+Software-unpoison page at PFN echoed into this file. This
+way a page can be reused again.
+This only works for Linux injected failures, not for real
+memory failures.
+
+Note these injection interfaces are not stable and might change between
+kernel versions
+
+corrupt-filter-dev-major
+corrupt-filter-dev-minor
+
+Only handle memory failures to pages associated with the file system defined
+by block device major/minor.  -1U is the wildcard value.
+This should be only used for testing with artificial injection.
+
+corrupt-filter-memcg
+
+Limit injection to pages owned by memgroup. Specified by inode number
+of the memcg.
+
+Example:
+        mkdir /cgroup/hwpoison
+
+        usemem -m 100 -s 1000 &
+        echo `jobs -p` > /cgroup/hwpoison/tasks
+
+        memcg_ino=$(ls -id /cgroup/hwpoison | cut -f1 -d' ')
+        echo $memcg_ino > /debug/hwpoison/corrupt-filter-memcg
+
+        page-types -p `pidof init`   --hwpoison  # shall do nothing
+        page-types -p `pidof usemem` --hwpoison  # poison its pages
+
+corrupt-filter-flags-mask
+corrupt-filter-flags-value
+
+When specified, only poison pages if ((page_flags & mask) == value).
+This allows stress testing of many kinds of pages. The page_flags
+are the same as in /proc/kpageflags. The flag bits are defined in
+include/linux/kernel-page-flags.h and documented in
+Documentation/vm/pagemap.txt
 
 Architecture specific MCE injector
 
diff --git a/Documentation/vm/page-types.c b/Documentation/vm/page-types.c
index 7a7d9bab32ef..66e9358e2144 100644
--- a/Documentation/vm/page-types.c
+++ b/Documentation/vm/page-types.c
@@ -1,11 +1,22 @@
 /*
  * page-types: Tool for querying page flags
  *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; version 2.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should find a copy of v2 of the GNU General Public License somewhere on
+ * your Linux system; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
  * Copyright (C) 2009 Intel corporation
  *
  * Authors: Wu Fengguang <fengguang.wu@intel.com>
- *
- * Released under the General Public License (GPL).
  */
 
 #define _LARGEFILE64_SOURCE