5 files changed, 77 insertions, 40 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 2418b6e71a85..8bd9cfdc70d7 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2039,7 +2039,7 @@ static int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk,
 
                 /* @tsk either already exited or can't exit until the end */
                 if (tsk->flags & PF_EXITING)
-                        continue;
+                        goto next;
 
                 /* as per above, nr_threads may decrease, but not increase. */
                 BUG_ON(i >= group_size);
@@ -2047,7 +2047,7 @@ static int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk,
                 ent.cgrp = task_cgroup_from_root(tsk, root);
                 /* nothing to do if this task is already in the cgroup */
                 if (ent.cgrp == cgrp)
-                        continue;
+                        goto next;
                 /*
                  * saying GFP_ATOMIC has no effect here because we did prealloc
                  * earlier, but it's good form to communicate our expectations.
@@ -2055,7 +2055,7 @@ static int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk,
                 retval = flex_array_put(group, i, &ent, GFP_ATOMIC);
                 BUG_ON(retval != 0);
                 i++;
-
+        next:
                 if (!threadgroup)
                         break;
         } while_each_thread(leader, tsk);
@@ -3188,11 +3188,9 @@ css_next_descendant_post(struct cgroup_subsys_state *pos,
 
         WARN_ON_ONCE(!rcu_read_lock_held());
 
-        /* if first iteration, visit the leftmost descendant */
-        if (!pos) {
-                next = css_leftmost_descendant(root);
-                return next != root ? next : NULL;
-        }
+        /* if first iteration, visit leftmost descendant which may be @root */
+        if (!pos)
+                return css_leftmost_descendant(root);
 
         /* if we visited @root, we're done */
         if (pos == root)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index d49a9d29334c..953c14348375 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -6767,6 +6767,10 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr,
         if (ret)
                 return -EFAULT;
 
+        /* disabled for now */
+        if (attr->mmap2)
+                return -EINVAL;
+
         if (attr->__reserved_1)
                 return -EINVAL;
 
diff --git a/kernel/mutex.c b/kernel/mutex.c
index 6d647aedffea..d24105b1b794 100644
--- a/kernel/mutex.c
+++ b/kernel/mutex.c
@@ -410,7 +410,7 @@ ww_mutex_set_context_fastpath(struct ww_mutex *lock,
 static __always_inline int __sched
 __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
                     struct lockdep_map *nest_lock, unsigned long ip,
-                    struct ww_acquire_ctx *ww_ctx)
+                    struct ww_acquire_ctx *ww_ctx, const bool use_ww_ctx)
 {
         struct task_struct *task = current;
         struct mutex_waiter waiter;
@@ -450,7 +450,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
                 struct task_struct *owner;
                 struct mspin_node  node;
 
-                if (!__builtin_constant_p(ww_ctx == NULL) && ww_ctx->acquired > 0) {
+                if (use_ww_ctx && ww_ctx->acquired > 0) {
                         struct ww_mutex *ww;
 
                         ww = container_of(lock, struct ww_mutex, base);
@@ -480,7 +480,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
                 if ((atomic_read(&lock->count) == 1) &&
                     (atomic_cmpxchg(&lock->count, 1, 0) == 1)) {
                         lock_acquired(&lock->dep_map, ip);
-                        if (!__builtin_constant_p(ww_ctx == NULL)) {
+                        if (use_ww_ctx) {
                                 struct ww_mutex *ww;
                                 ww = container_of(lock, struct ww_mutex, base);
 
@@ -551,7 +551,7 @@ slowpath:
                         goto err;
                 }
 
-                if (!__builtin_constant_p(ww_ctx == NULL) && ww_ctx->acquired > 0) {
+                if (use_ww_ctx && ww_ctx->acquired > 0) {
                         ret = __mutex_lock_check_stamp(lock, ww_ctx);
                         if (ret)
                                 goto err;
@@ -575,7 +575,7 @@ skip_wait:
         lock_acquired(&lock->dep_map, ip);
         mutex_set_owner(lock);
 
-        if (!__builtin_constant_p(ww_ctx == NULL)) {
+        if (use_ww_ctx) {
                 struct ww_mutex *ww = container_of(lock, struct ww_mutex, base);
                 struct mutex_waiter *cur;
 
@@ -615,7 +615,7 @@ mutex_lock_nested(struct mutex *lock, unsigned int subclass)
 {
         might_sleep();
         __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE,
-                            subclass, NULL, _RET_IP_, NULL);
+                            subclass, NULL, _RET_IP_, NULL, 0);
 }
 
 EXPORT_SYMBOL_GPL(mutex_lock_nested);
@@ -625,7 +625,7 @@ _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest)
 {
         might_sleep();
         __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE,
-                            0, nest, _RET_IP_, NULL);
+                            0, nest, _RET_IP_, NULL, 0);
 }
 
 EXPORT_SYMBOL_GPL(_mutex_lock_nest_lock);
@@ -635,7 +635,7 @@ mutex_lock_killable_nested(struct mutex *lock, unsigned int subclass)
 {
         might_sleep();
         return __mutex_lock_common(lock, TASK_KILLABLE,
-                                   subclass, NULL, _RET_IP_, NULL);
+                                   subclass, NULL, _RET_IP_, NULL, 0);
 }
 EXPORT_SYMBOL_GPL(mutex_lock_killable_nested);
 
@@ -644,7 +644,7 @@ mutex_lock_interruptible_nested(struct mutex *lock, unsigned int subclass)
 {
         might_sleep();
         return __mutex_lock_common(lock, TASK_INTERRUPTIBLE,
-                                   subclass, NULL, _RET_IP_, NULL);
+                                   subclass, NULL, _RET_IP_, NULL, 0);
 }
 
 EXPORT_SYMBOL_GPL(mutex_lock_interruptible_nested);
@@ -682,7 +682,7 @@ __ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
 
         might_sleep();
         ret =  __mutex_lock_common(&lock->base, TASK_UNINTERRUPTIBLE,
-                                   0, &ctx->dep_map, _RET_IP_, ctx);
+                                   0, &ctx->dep_map, _RET_IP_, ctx, 1);
         if (!ret && ctx->acquired > 1)
                 return ww_mutex_deadlock_injection(lock, ctx);
 
@@ -697,7 +697,7 @@ __ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
 
         might_sleep();
         ret = __mutex_lock_common(&lock->base, TASK_INTERRUPTIBLE,
-                                  0, &ctx->dep_map, _RET_IP_, ctx);
+                                  0, &ctx->dep_map, _RET_IP_, ctx, 1);
 
         if (!ret && ctx->acquired > 1)
                 return ww_mutex_deadlock_injection(lock, ctx);
@@ -809,28 +809,28 @@ __mutex_lock_slowpath(atomic_t *lock_count)