HWPOISON: Add simple debugfs interface to inject hwpoison on arbitary PFNs
Useful for some testing scenarios, although specific testing is often
done better through MADV_POISON
This can be done with the x86 level MCE injector too, but this interface
allows it to do independently from low level x86 changes.
v2: Add module license (Haicheng Li)
Signed-off-by: Andi Kleen <ak@linux.intel.com>
diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c
new file mode 100644
index 0000000..e1d8513
--- /dev/null
+++ b/mm/hwpoison-inject.c
@@ -0,0 +1,41 @@
+/* Inject a hwpoison memory failure on a arbitary pfn */
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+
+static struct dentry *hwpoison_dir, *corrupt_pfn;
+
+static int hwpoison_inject(void *data, u64 val)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ printk(KERN_INFO "Injecting memory failure at pfn %Lx\n", val);
+ return __memory_failure(val, 18, 0);
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(hwpoison_fops, NULL, hwpoison_inject, "%lli\n");
+
+static void pfn_inject_exit(void)
+{
+ if (hwpoison_dir)
+ debugfs_remove_recursive(hwpoison_dir);
+}
+
+static int pfn_inject_init(void)
+{
+ hwpoison_dir = debugfs_create_dir("hwpoison", NULL);
+ if (hwpoison_dir == NULL)
+ return -ENOMEM;
+ corrupt_pfn = debugfs_create_file("corrupt-pfn", 0600, hwpoison_dir,
+ NULL, &hwpoison_fops);
+ if (corrupt_pfn == NULL) {
+ pfn_inject_exit();
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+module_init(pfn_inject_init);
+module_exit(pfn_inject_exit);
+MODULE_LICENSE("GPL");