From 478c5ffc0b50527bd2390f2daa46cc16276b8413 Mon Sep 17 00:00:00 2001 From: Wu Fengguang Date: Wed, 16 Dec 2009 12:19:59 +0100 Subject: 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 Signed-off-by: Wu Fengguang Signed-off-by: Andi Kleen --- mm/Kconfig | 1 + mm/hwpoison-inject.c | 10 ++++++++++ mm/internal.h | 2 ++ mm/memory-failure.c | 20 ++++++++++++++++++++ 4 files changed, 33 insertions(+) (limited to 'mm') diff --git a/mm/Kconfig b/mm/Kconfig index 2310984591e..8cea7fde06e 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" diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c index 2b6b3200fa6..c4dfd89f654 100644 --- a/mm/hwpoison-inject.c +++ b/mm/hwpoison-inject.c @@ -102,6 +102,16 @@ static int pfn_inject_init(void) 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 04bbce8b8ba..b2027c73119 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -255,3 +255,5 @@ extern int hwpoison_filter(struct page *p); 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 82ac73436d0..22d2b2028e5 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #include #include @@ -50,8 +51,12 @@ atomic_long_t mce_bad_pages __read_mostly = ATOMIC_LONG_INIT(0); 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 @@ static int hwpoison_filter_dev(struct page *p) 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); -- cgit v1.2.3-18-g5258