diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c
index c1cdc923666..90723e65b08 100644
--- a/drivers/firmware/memmap.c
+++ b/drivers/firmware/memmap.c
@@ -237,7 +237,7 @@ static ssize_t memmap_attr_show(struct kobject *kobj,
  * firmware_map_add() or firmware_map_add_early() afterwards, the entries
  * are not added to sysfs.
  */
-static int __init memmap_init(void)
+static int __init firmware_memmap_init(void)
 {
 	struct firmware_map_entry *entry;
 
@@ -246,5 +246,5 @@ static int __init memmap_init(void)
 
 	return 0;
 }
-late_initcall(memmap_init);
+late_initcall(firmware_memmap_init);
 
diff --git a/drivers/video/backlight/lm3639_bl.c b/drivers/video/backlight/lm3639_bl.c
index c6915c6c3cd..585949b5705 100644
--- a/drivers/video/backlight/lm3639_bl.c
+++ b/drivers/video/backlight/lm3639_bl.c
@@ -206,11 +206,11 @@ static ssize_t lm3639_bled_mode_store(struct device *dev,
 
 out:
 	dev_err(pchip->dev, "%s:i2c access fail to register\n", __func__);
-	return size;
+	return ret;
 
 out_input:
 	dev_err(pchip->dev, "%s:input conversion fail\n", __func__);
-	return size;
+	return ret;
 
 }
 
diff --git a/include/linux/coredump.h b/include/linux/coredump.h
index 1775eb8acc0..1d7399314a8 100644
--- a/include/linux/coredump.h
+++ b/include/linux/coredump.h
@@ -4,6 +4,7 @@
 #include <linux/types.h>
 #include <linux/mm.h>
 #include <linux/fs.h>
+#include <asm/siginfo.h>
 
 /*
  * These are the only things you should do on a core-file: use only these
diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h
index 00474b04714..65e3e87eacc 100644
--- a/include/linux/pid_namespace.h
+++ b/include/linux/pid_namespace.h
@@ -47,15 +47,9 @@ static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
 }
 
 extern struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *ns);
-extern void free_pid_ns(struct kref *kref);
 extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
 extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
-
-static inline void put_pid_ns(struct pid_namespace *ns)
-{
-	if (ns != &init_pid_ns)
-		kref_put(&ns->kref, free_pid_ns);
-}
+extern void put_pid_ns(struct pid_namespace *ns);
 
 #else /* !CONFIG_PID_NS */
 #include <linux/err.h>
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index 478bad2745e..eb00be20581 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -133,19 +133,26 @@ struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *old
 	return create_pid_namespace(old_ns);
 }
 
-void free_pid_ns(struct kref *kref)
+static void free_pid_ns(struct kref *kref)
 {
-	struct pid_namespace *ns, *parent;
+	struct pid_namespace *ns;
 
 	ns = container_of(kref, struct pid_namespace, kref);
-
-	parent = ns->parent;
 	destroy_pid_namespace(ns);
-
-	if (parent != NULL)
-		put_pid_ns(parent);
 }
-EXPORT_SYMBOL_GPL(free_pid_ns);
+
+void put_pid_ns(struct pid_namespace *ns)
+{
+	struct pid_namespace *parent;
+
+	while (ns != &init_pid_ns) {
+		parent = ns->parent;
+		if (!kref_put(&ns->kref, free_pid_ns))
+			break;
+		ns = parent;
+	}
+}
+EXPORT_SYMBOL_GPL(put_pid_ns);
 
 void zap_pid_ns_processes(struct pid_namespace *pid_ns)
 {
diff --git a/kernel/sys.c b/kernel/sys.c
index c5cb5b99cb8..01865c6fb6a 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1265,15 +1265,16 @@ DECLARE_RWSEM(uts_sem);
  * Work around broken programs that cannot handle "Linux 3.0".
  * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
  */
-static int override_release(char __user *release, int len)
+static int override_release(char __user *release, size_t len)
 {
 	int ret = 0;
-	char buf[65];
 
 	if (current->personality & UNAME26) {
-		char *rest = UTS_RELEASE;
+		const char *rest = UTS_RELEASE;
+		char buf[65] = { 0 };
 		int ndots = 0;
 		unsigned v;
+		size_t copy;
 
 		while (*rest) {
 			if (*rest == '.' && ++ndots >= 3)
@@ -1283,8 +1284,9 @@ static int override_release(char __user *release, int len)
 			rest++;
 		}
 		v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 40;
-		snprintf(buf, len, "2.6.%u%s", v, rest);
-		ret = copy_to_user(release, buf, len);
+		copy = min(sizeof(buf), max_t(size_t, 1, len));
+		copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
+		ret = copy_to_user(release, buf, copy + 1);
 	}
 	return ret;
 }
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index b9087bff008..d84beb994f3 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -264,7 +264,7 @@ static struct dma_debug_entry *__hash_bucket_find(struct hash_bucket *bucket,
 						  match_fn match)
 {
 	struct dma_debug_entry *entry, *ret = NULL;
-	int matches = 0, match_lvl, last_lvl = 0;
+	int matches = 0, match_lvl, last_lvl = -1;
 
 	list_for_each_entry(entry, &bucket->list, list) {
 		if (!match(ref, entry))
@@ -293,7 +293,7 @@ static struct dma_debug_entry *__hash_bucket_find(struct hash_bucket *bucket,
 		} else if (match_lvl > last_lvl) {
 			/*
 			 * We found an entry that fits better then the
-			 * previous one
+			 * previous one or it is the 1st match.
 			 */
 			last_lvl = match_lvl;
 			ret      = entry;
diff --git a/mm/compaction.c b/mm/compaction.c
index 2c4ce17651d..9eef55838fc 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -346,7 +346,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
 	 * pages requested were isolated. If there were any failures, 0 is
 	 * returned and CMA will fail.
 	 */
-	if (strict && nr_strict_required != total_isolated)
+	if (strict && nr_strict_required > total_isolated)
 		total_isolated = 0;
 
 	if (locked)