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authorWu Fengguang <fengguang.wu@intel.com>2009-12-16 12:19:59 +0100
committerAndi Kleen <ak@linux.intel.com>2009-12-16 12:19:59 +0100
commit7c116f2b0dbac4a1dd051c7a5e8cef37701cafd4 (patch)
treeac7f1e56551df46bc79e400a182a57f4eae5ddaf
parent138ce286eb6ee6d39ca4fb50516e93adaf6b605f (diff)
HWPOISON: add fs/device filters
Filesystem data/metadata present the most tricky-to-isolate pages. It requires careful code review and stress testing to get them right. The fs/device filter helps to target the stress tests to some specific filesystem pages. The filter condition is block device's major/minor numbers: - corrupt-filter-dev-major - corrupt-filter-dev-minor When specified (non -1), only page cache pages that belong to that device will be poisoned. The filters are checked reliably on the locked and refcounted page. Haicheng: clear PG_hwpoison and drop bad page count if filter not OK AK: Add documentation CC: Haicheng Li <haicheng.li@intel.com> CC: Nick Piggin <npiggin@suse.de> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com>
-rw-r--r--Documentation/vm/hwpoison.txt7
-rw-r--r--mm/hwpoison-inject.c11
-rw-r--r--mm/internal.h3
-rw-r--r--mm/memory-failure.c51
4 files changed, 72 insertions, 0 deletions
diff --git a/Documentation/vm/hwpoison.txt b/Documentation/vm/hwpoison.txt
index f047e75acb2..fdf58046432 100644
--- a/Documentation/vm/hwpoison.txt
+++ b/Documentation/vm/hwpoison.txt
@@ -115,6 +115,13 @@ 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.
+
Architecture specific MCE injector
x86 has mce-inject, mce-test
diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c
index 6e35e563bf5..ac692a9b766 100644
--- a/mm/hwpoison-inject.c
+++ b/mm/hwpoison-inject.c
@@ -3,6 +3,7 @@
#include <linux/debugfs.h>
#include <linux/kernel.h>
#include <linux/mm.h>
+#include "internal.h"
static struct dentry *hwpoison_dir;
@@ -54,6 +55,16 @@ static int pfn_inject_init(void)
if (!dentry)
goto fail;
+ dentry = debugfs_create_u32("corrupt-filter-dev-major", 0600,
+ hwpoison_dir, &hwpoison_filter_dev_major);
+ if (!dentry)
+ goto fail;
+
+ dentry = debugfs_create_u32("corrupt-filter-dev-minor", 0600,
+ hwpoison_dir, &hwpoison_filter_dev_minor);
+ if (!dentry)
+ goto fail;
+
return 0;
fail:
pfn_inject_exit();
diff --git a/mm/internal.h b/mm/internal.h
index 49b2ff776b7..814da335f05 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -250,3 +250,6 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
#define ZONE_RECLAIM_SOME 0
#define ZONE_RECLAIM_SUCCESS 1
#endif
+
+extern u32 hwpoison_filter_dev_major;
+extern u32 hwpoison_filter_dev_minor;
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index edeaf2319e7..82ac73436d0 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -48,6 +48,50 @@ int sysctl_memory_failure_recovery __read_mostly = 1;
atomic_long_t mce_bad_pages __read_mostly = ATOMIC_LONG_INIT(0);
+u32 hwpoison_filter_dev_major = ~0U;
+u32 hwpoison_filter_dev_minor = ~0U;
+EXPORT_SYMBOL_GPL(hwpoison_filter_dev_major);
+EXPORT_SYMBOL_GPL(hwpoison_filter_dev_minor);
+
+static int hwpoison_filter_dev(struct page *p)
+{
+ struct address_space *mapping;
+ dev_t dev;
+
+ if (hwpoison_filter_dev_major == ~0U &&
+ hwpoison_filter_dev_minor == ~0U)
+ return 0;
+
+ /*
+ * page_mapping() does not accept slab page
+ */
+ if (PageSlab(p))
+ return -EINVAL;
+
+ mapping = page_mapping(p);
+ if (mapping == NULL || mapping->host == NULL)
+ return -EINVAL;
+
+ dev = mapping->host->i_sb->s_dev;
+ if (hwpoison_filter_dev_major != ~0U &&
+ hwpoison_filter_dev_major != MAJOR(dev))
+ return -EINVAL;
+ if (hwpoison_filter_dev_minor != ~0U &&
+ hwpoison_filter_dev_minor != MINOR(dev))
+ return -EINVAL;
+
+ return 0;
+}
+
+int hwpoison_filter(struct page *p)
+{
+ if (hwpoison_filter_dev(p))
+ return -EINVAL;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hwpoison_filter);
+
/*
* Send all the processes who have the page mapped an ``action optional''
* signal.
@@ -843,6 +887,13 @@ int __memory_failure(unsigned long pfn, int trapno, int flags)
res = 0;
goto out;
}
+ if (hwpoison_filter(p)) {
+ if (TestClearPageHWPoison(p))
+ atomic_long_dec(&mce_bad_pages);
+ unlock_page(p);
+ put_page(p);
+ return 0;
+ }
wait_on_page_writeback(p);