v4.19.13 snapshot.
diff --git a/mm/failslab.c b/mm/failslab.c
new file mode 100644
index 0000000..b135ebb
--- /dev/null
+++ b/mm/failslab.c
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/fault-inject.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include "slab.h"
+
+static struct {
+ struct fault_attr attr;
+ bool ignore_gfp_reclaim;
+ bool cache_filter;
+} failslab = {
+ .attr = FAULT_ATTR_INITIALIZER,
+ .ignore_gfp_reclaim = true,
+ .cache_filter = false,
+};
+
+bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags)
+{
+ /* No fault-injection for bootstrap cache */
+ if (unlikely(s == kmem_cache))
+ return false;
+
+ if (gfpflags & __GFP_NOFAIL)
+ return false;
+
+ if (failslab.ignore_gfp_reclaim && (gfpflags & __GFP_RECLAIM))
+ return false;
+
+ if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))
+ return false;
+
+ return should_fail(&failslab.attr, s->object_size);
+}
+
+static int __init setup_failslab(char *str)
+{
+ return setup_fault_attr(&failslab.attr, str);
+}
+__setup("failslab=", setup_failslab);
+
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+static int __init failslab_debugfs_init(void)
+{
+ struct dentry *dir;
+ umode_t mode = S_IFREG | 0600;
+
+ dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
+ if (IS_ERR(dir))
+ return PTR_ERR(dir);
+
+ if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
+ &failslab.ignore_gfp_reclaim))
+ goto fail;
+ if (!debugfs_create_bool("cache-filter", mode, dir,
+ &failslab.cache_filter))
+ goto fail;
+
+ return 0;
+fail:
+ debugfs_remove_recursive(dir);
+
+ return -ENOMEM;
+}
+
+late_initcall(failslab_debugfs_init);
+
+#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */