Merge tag 'v4.4.24' into android-4.4.y

This is the 4.4.24 stable release

5 files changed, 85 insertions, 14 deletions

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index e5bd044c1cbb..85737aada4d2 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -325,8 +325,7 @@ static struct file_system_type cpuset_fs_type = {
 /*
  * Return in pmask the portion of a cpusets's cpus_allowed that
  * are online.  If none are online, walk up the cpuset hierarchy
- * until we find one that does have some online cpus.  The top
- * cpuset always has some cpus online.
+ * until we find one that does have some online cpus.
  *
  * One way or another, we guarantee to return some non-empty subset
  * of cpu_online_mask.
@@ -335,8 +334,20 @@ static struct file_system_type cpuset_fs_type = {
  */
 static void guarantee_online_cpus(struct cpuset *cs, struct cpumask *pmask)
 {
-	while (!cpumask_intersects(cs->effective_cpus, cpu_online_mask))
+	while (!cpumask_intersects(cs->effective_cpus, cpu_online_mask)) {
 		cs = parent_cs(cs);
+		if (unlikely(!cs)) {
+			/*
+			 * The top cpuset doesn't have any online cpu as a
+			 * consequence of a race between cpuset_hotplug_work
+			 * and cpu hotplug notifier.  But we know the top
+			 * cpuset's effective_cpus is on its way to to be
+			 * identical to cpu_online_mask.
+			 */
+			cpumask_copy(pmask, cpu_online_mask);
+			return;
+		}
+	}
 	cpumask_and(pmask, cs->effective_cpus, cpu_online_mask);
 }
 
diff --git a/kernel/events/core.c b/kernel/events/core.c
index cf9dfbc15403..541ea712ad98 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1544,12 +1544,33 @@ static int __init perf_workqueue_init(void)
 
 core_initcall(perf_workqueue_init);
 
-static inline int pmu_filter_match(struct perf_event *event)
+static inline int __pmu_filter_match(struct perf_event *event)
 {
 	struct pmu *pmu = event->pmu;
 	return pmu->filter_match ? pmu->filter_match(event) : 1;
 }
 
+/*
+ * Check whether we should attempt to schedule an event group based on
+ * PMU-specific filtering. An event group can consist of HW and SW events,
+ * potentially with a SW leader, so we must check all the filters, to
+ * determine whether a group is schedulable:
+ */
+static inline int pmu_filter_match(struct perf_event *event)
+{
+	struct perf_event *child;
+
+	if (!__pmu_filter_match(event))
+		return 0;
+
+	list_for_each_entry(child, &event->sibling_list, group_entry) {
+		if (!__pmu_filter_match(child))
+			return 0;
+	}
+
+	return 1;
+}
+
 static inline int
 event_filter_match(struct perf_event *event)
 {
diff --git a/kernel/fork.c b/kernel/fork.c
index a1d163250909..18a5cb17035a 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -902,14 +902,12 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
 	deactivate_mm(tsk, mm);
 
 	/*
-	 * If we're exiting normally, clear a user-space tid field if
-	 * requested.  We leave this alone when dying by signal, to leave
-	 * the value intact in a core dump, and to save the unnecessary
-	 * trouble, say, a killed vfork parent shouldn't touch this mm.
-	 * Userland only wants this done for a sys_exit.
+	 * Signal userspace if we're not exiting with a core dump
+	 * because we want to leave the value intact for debugging
+	 * purposes.
 	 */
 	if (tsk->clear_child_tid) {
-		if (!(tsk->flags & PF_SIGNALED) &&
+		if (!(tsk->signal->flags & SIGNAL_GROUP_COREDUMP) &&
 		    atomic_read(&mm->mm_users) > 1) {
 			/*
 			 * We don't check the error code - if userspace has
diff --git a/kernel/printk/braille.c b/kernel/printk/braille.c
index 276762f3a460..d5760c42f042 100644
--- a/kernel/printk/braille.c
+++ b/kernel/printk/braille.c
@@ -9,10 +9,10 @@
 
 char *_braille_console_setup(char **str, char **brl_options)
 {
-	if (!memcmp(*str, "brl,", 4)) {
+	if (!strncmp(*str, "brl,", 4)) {
 		*brl_options = "";
 		*str += 4;
-	} else if (!memcmp(str, "brl=", 4)) {
+	} else if (!strncmp(*str, "brl=", 4)) {
 		*brl_options = *str + 4;
 		*str = strchr(*brl_options, ',');
 		if (!*str)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index d964422eb601..abb795e8a6f1 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2155,6 +2155,21 @@ static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
 	return 0;
 }
 
+static int do_proc_douintvec_conv(bool *negp, unsigned long *lvalp,
+				 int *valp,
+				 int write, void *data)
+{
+	if (write) {
+		if (*negp)
+			return -EINVAL;
+		*valp = *lvalp;
+	} else {
+		unsigned int val = *valp;
+		*lvalp = (unsigned long)val;
+	}
+	return 0;
+}
+
 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
 
 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
@@ -2282,8 +2297,27 @@ static int do_proc_dointvec(struct ctl_table *table, int write,
 int proc_dointvec(struct ctl_table *table, int write,
 		     void __user *buffer, size_t *lenp, loff_t *ppos)
 {
-    return do_proc_dointvec(table,write,buffer,lenp,ppos,
-		    	    NULL,NULL);
+	return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
+}
+
+/**
+ * proc_douintvec - read a vector of unsigned integers
+ * @table: the sysctl table
+ * @write: %TRUE if this is a write to the sysctl file
+ * @buffer: the user buffer
+ * @lenp: the size of the user buffer
+ * @ppos: file position
+ *
+ * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
+ * values from/to the user buffer, treated as an ASCII string.
+ *
+ * Returns 0 on success.
+ */
+int proc_douintvec(struct ctl_table *table, int write,
+		     void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	return do_proc_dointvec(table, write, buffer, lenp, ppos,
+				do_proc_douintvec_conv, NULL);
 }
 
 /*
@@ -2896,6 +2930,12 @@ int proc_dointvec(struct ctl_table *table, int write,
 	return -ENOSYS;
 }
 
+int proc_douintvec(struct ctl_table *table, int write,
+		  void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	return -ENOSYS;
+}
+
 int proc_dointvec_minmax(struct ctl_table *table, int write,
 		    void __user *buffer, size_t *lenp, loff_t *ppos)
 {
@@ -2941,6 +2981,7 @@ int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
  * exception granted :-)
  */
 EXPORT_SYMBOL(proc_dointvec);
+EXPORT_SYMBOL(proc_douintvec);
 EXPORT_SYMBOL(proc_dointvec_jiffies);
 EXPORT_SYMBOL(proc_dointvec_minmax);
 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);