Merge branch 'origin'

4 files changed, 26 insertions, 17 deletions

diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 7732199..7712912 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -114,16 +114,16 @@ rcu_torture_alloc(void)
 {
 	struct list_head *p;
 
-	spin_lock(&rcu_torture_lock);
+	spin_lock_bh(&rcu_torture_lock);
 	if (list_empty(&rcu_torture_freelist)) {
 		atomic_inc(&n_rcu_torture_alloc_fail);
-		spin_unlock(&rcu_torture_lock);
+		spin_unlock_bh(&rcu_torture_lock);
 		return NULL;
 	}
 	atomic_inc(&n_rcu_torture_alloc);
 	p = rcu_torture_freelist.next;
 	list_del_init(p);
-	spin_unlock(&rcu_torture_lock);
+	spin_unlock_bh(&rcu_torture_lock);
 	return container_of(p, struct rcu_torture, rtort_free);
 }
 
@@ -134,9 +134,9 @@ static void
 rcu_torture_free(struct rcu_torture *p)
 {
 	atomic_inc(&n_rcu_torture_free);
-	spin_lock(&rcu_torture_lock);
+	spin_lock_bh(&rcu_torture_lock);
 	list_add_tail(&p->rtort_free, &rcu_torture_freelist);
-	spin_unlock(&rcu_torture_lock);
+	spin_unlock_bh(&rcu_torture_lock);
 }
 
 static void
diff --git a/kernel/sched.c b/kernel/sched.c
index 3ee2ae4..ec7fd9c 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -5141,7 +5141,7 @@ static void init_sched_build_groups(struct sched_group groups[], cpumask_t span,
 #define SEARCH_SCOPE		2
 #define MIN_CACHE_SIZE		(64*1024U)
 #define DEFAULT_CACHE_SIZE	(5*1024*1024U)
-#define ITERATIONS		2
+#define ITERATIONS		1
 #define SIZE_THRESH		130
 #define COST_THRESH		130
 
@@ -5480,9 +5480,9 @@ static unsigned long long measure_migration_cost(int cpu1, int cpu2)
 				break;
 			}
 		/*
-		 * Increase the cachesize in 5% steps:
+		 * Increase the cachesize in 10% steps:
 		 */
-		size = size * 20 / 19;
+		size = size * 10 / 9;
 	}
 
 	if (migration_debug)
diff --git a/kernel/time.c b/kernel/time.c
index 7477b1d..1f23e68 100644
--- a/kernel/time.c
+++ b/kernel/time.c
@@ -155,7 +155,7 @@ int do_sys_settimeofday(struct timespec *tv, struct timezone *tz)
 	static int firsttime = 1;
 	int error = 0;
 
-	if (!timespec_valid(tv))
+	if (tv && !timespec_valid(tv))
 		return -EINVAL;
 
 	error = security_settime(tv, tz);
diff --git a/kernel/user.c b/kernel/user.c
index 89e562f..d1ae234 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -13,6 +13,7 @@
 #include <linux/slab.h>
 #include <linux/bitops.h>
 #include <linux/key.h>
+#include <linux/interrupt.h>
 
 /*
  * UID task count cache, to get fast user lookup in "alloc_uid"
@@ -27,6 +28,12 @@
 
 static kmem_cache_t *uid_cachep;
 static struct list_head uidhash_table[UIDHASH_SZ];
+
+/*
+ * The uidhash_lock is mostly taken from process context, but it is
+ * occasionally also taken from softirq/tasklet context, when
+ * task-structs get RCU-freed. Hence all locking must be softirq-safe.
+ */
 static DEFINE_SPINLOCK(uidhash_lock);
 
 struct user_struct root_user = {
@@ -83,14 +90,15 @@ struct user_struct *find_user(uid_t uid)
 {
 	struct user_struct *ret;
 
-	spin_lock(&uidhash_lock);
+	spin_lock_bh(&uidhash_lock);
 	ret = uid_hash_find(uid, uidhashentry(uid));
-	spin_unlock(&uidhash_lock);
+	spin_unlock_bh(&uidhash_lock);
 	return ret;
 }
 
 void free_uid(struct user_struct *up)
 {
+	local_bh_disable();
 	if (up && atomic_dec_and_lock(&up->__count, &uidhash_lock)) {
 		uid_hash_remove(up);
 		key_put(up->uid_keyring);
@@ -98,6 +106,7 @@ void free_uid(struct user_struct *up)
 		kmem_cache_free(uid_cachep, up);
 		spin_unlock(&uidhash_lock);
 	}
+	local_bh_enable();
 }
 
 struct user_struct * alloc_uid(uid_t uid)
@@ -105,9 +114,9 @@ struct user_struct * alloc_uid(uid_t uid)
 	struct list_head *hashent = uidhashentry(uid);
 	struct user_struct *up;
 
-	spin_lock(&uidhash_lock);
+	spin_lock_bh(&uidhash_lock);
 	up = uid_hash_find(uid, hashent);
-	spin_unlock(&uidhash_lock);
+	spin_unlock_bh(&uidhash_lock);
 
 	if (!up) {
 		struct user_struct *new;
@@ -137,7 +146,7 @@ struct user_struct * alloc_uid(uid_t uid)
 		 * Before adding this, check whether we raced
 		 * on adding the same user already..
 		 */
-		spin_lock(&uidhash_lock);
+		spin_lock_bh(&uidhash_lock);
 		up = uid_hash_find(uid, hashent);
 		if (up) {
 			key_put(new->uid_keyring);
@@ -147,7 +156,7 @@ struct user_struct * alloc_uid(uid_t uid)
 			uid_hash_insert(new, hashent);
 			up = new;
 		}
-		spin_unlock(&uidhash_lock);
+		spin_unlock_bh(&uidhash_lock);
 
 	}
 	return up;
@@ -183,9 +192,9 @@ static int __init uid_cache_init(void)
 		INIT_LIST_HEAD(uidhash_table + n);
 
 	/* Insert the root user immediately (init already runs as root) */
-	spin_lock(&uidhash_lock);
+	spin_lock_bh(&uidhash_lock);
 	uid_hash_insert(&root_user, uidhashentry(0));
-	spin_unlock(&uidhash_lock);
+	spin_unlock_bh(&uidhash_lock);
 
 	return 0;
 }