HWPOISON: add page flags filter
When specified, only poison pages if ((page_flags & mask) == value).
- corrupt-filter-flags-mask
- corrupt-filter-flags-value
This allows stress testing of many kinds of pages.
Strictly speaking, the buddy pages requires taking zone lock, to avoid
setting PG_hwpoison on a "was buddy but now allocated to someone" page.
However we can just do nothing because we set PG_locked in the beginning,
this prevents the page allocator from allocating it to someone. (It will
BUG() on the unexpected PG_locked, which is fine for hwpoison testing.)
[AK: Add select PROC_PAGE_MONITOR to satisfy dependency]
CC: Nick Piggin <npiggin@suse.de>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
diff --git a/Documentation/vm/hwpoison.txt b/Documentation/vm/hwpoison.txt
index 4ef7bb3..f454d3c 100644
--- a/Documentation/vm/hwpoison.txt
+++ b/Documentation/vm/hwpoison.txt
@@ -123,6 +123,16 @@
by block device major/minor. -1U is the wildcard value.
This should be only used for testing with artificial injection.
+
+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
x86 has mce-inject, mce-test
diff --git a/mm/Kconfig b/mm/Kconfig
index 2310984..8cea7fd 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -253,6 +253,7 @@
config HWPOISON_INJECT
tristate "Poison pages injector"
depends on MEMORY_FAILURE && DEBUG_KERNEL
+ select PROC_PAGE_MONITOR
config NOMMU_INITIAL_TRIM_EXCESS
int "Turn on mmap() excess space trimming before booting"
diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c
index 2b6b320..c4dfd89 100644
--- a/mm/hwpoison-inject.c
+++ b/mm/hwpoison-inject.c
@@ -102,6 +102,16 @@
if (!dentry)
goto fail;
+ dentry = debugfs_create_u64("corrupt-filter-flags-mask", 0600,
+ hwpoison_dir, &hwpoison_filter_flags_mask);
+ if (!dentry)
+ goto fail;
+
+ dentry = debugfs_create_u64("corrupt-filter-flags-value", 0600,
+ hwpoison_dir, &hwpoison_filter_flags_value);
+ if (!dentry)
+ goto fail;
+
return 0;
fail:
pfn_inject_exit();
diff --git a/mm/internal.h b/mm/internal.h
index 04bbce8..b2027c7 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -255,3 +255,5 @@
extern u32 hwpoison_filter_dev_major;
extern u32 hwpoison_filter_dev_minor;
+extern u64 hwpoison_filter_flags_mask;
+extern u64 hwpoison_filter_flags_value;
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 82ac734..22d2b20 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -34,6 +34,7 @@
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/page-flags.h>
+#include <linux/kernel-page-flags.h>
#include <linux/sched.h>
#include <linux/ksm.h>
#include <linux/rmap.h>
@@ -50,8 +51,12 @@
u32 hwpoison_filter_dev_major = ~0U;
u32 hwpoison_filter_dev_minor = ~0U;
+u64 hwpoison_filter_flags_mask;
+u64 hwpoison_filter_flags_value;
EXPORT_SYMBOL_GPL(hwpoison_filter_dev_major);
EXPORT_SYMBOL_GPL(hwpoison_filter_dev_minor);
+EXPORT_SYMBOL_GPL(hwpoison_filter_flags_mask);
+EXPORT_SYMBOL_GPL(hwpoison_filter_flags_value);
static int hwpoison_filter_dev(struct page *p)
{
@@ -83,11 +88,26 @@
return 0;
}
+static int hwpoison_filter_flags(struct page *p)
+{
+ if (!hwpoison_filter_flags_mask)
+ return 0;
+
+ if ((stable_page_flags(p) & hwpoison_filter_flags_mask) ==
+ hwpoison_filter_flags_value)
+ return 0;
+ else
+ return -EINVAL;
+}
+
int hwpoison_filter(struct page *p)
{
if (hwpoison_filter_dev(p))
return -EINVAL;
+ if (hwpoison_filter_flags(p))
+ return -EINVAL;
+
return 0;
}
EXPORT_SYMBOL_GPL(hwpoison_filter);