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>

1 files changed, 1 insertions, 0 deletions

diff --git a/mm/Kconfig b/mm/Kconfig
index 2310984591ed..8cea7fde06e1 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -253,6 +253,7 @@ config MEMORY_FAILURE
 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"