Merge commit '6e64f4580381e32c06ee146ca807c555b8f73e24' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into gpio/for-next

1 files changed, 25 insertions, 4 deletions

diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index d2432df2b905..8708a1205f82 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -23,6 +23,7 @@
 #include <linux/sched/debug.h>
 #include <linux/sched/sysctl.h>
 #include <linux/hung_task.h>
+#include <linux/rwsem.h>
 
 #include <trace/events/sched.h>
 
@@ -100,6 +101,7 @@ static void debug_show_blocker(struct task_struct *task)
 {
 	struct task_struct *g, *t;
 	unsigned long owner, blocker, blocker_type;
+	const char *rwsem_blocked_by, *rwsem_blocked_as;
 
 	RCU_LOCKDEP_WARN(!rcu_read_lock_held(), "No rcu lock held");
 
@@ -111,12 +113,20 @@ static void debug_show_blocker(struct task_struct *task)
 
 	switch (blocker_type) {
 	case BLOCKER_TYPE_MUTEX:
-		owner = mutex_get_owner(
-			(struct mutex *)hung_task_blocker_to_lock(blocker));
+		owner = mutex_get_owner(hung_task_blocker_to_lock(blocker));
 		break;
 	case BLOCKER_TYPE_SEM:
-		owner = sem_last_holder(
-			(struct semaphore *)hung_task_blocker_to_lock(blocker));
+		owner = sem_last_holder(hung_task_blocker_to_lock(blocker));
+		break;
+	case BLOCKER_TYPE_RWSEM_READER:
+	case BLOCKER_TYPE_RWSEM_WRITER:
+		owner = (unsigned long)rwsem_owner(
+					hung_task_blocker_to_lock(blocker));
+		rwsem_blocked_as = (blocker_type == BLOCKER_TYPE_RWSEM_READER) ?
+					"reader" : "writer";
+		rwsem_blocked_by = is_rwsem_reader_owned(
+					hung_task_blocker_to_lock(blocker)) ?
+					"reader" : "writer";
 		break;
 	default:
 		WARN_ON_ONCE(1);
@@ -134,6 +144,11 @@ static void debug_show_blocker(struct task_struct *task)
 			pr_err("INFO: task %s:%d is blocked on a semaphore, but the last holder is not found.\n",
 			       task->comm, task->pid);
 			break;
+		case BLOCKER_TYPE_RWSEM_READER:
+		case BLOCKER_TYPE_RWSEM_WRITER:
+			pr_err("INFO: task %s:%d is blocked on an rw-semaphore, but the owner is not found.\n",
+			       task->comm, task->pid);
+			break;
 		}
 		return;
 	}
@@ -152,6 +167,12 @@ static void debug_show_blocker(struct task_struct *task)
 			pr_err("INFO: task %s:%d blocked on a semaphore likely last held by task %s:%d\n",
 			       task->comm, task->pid, t->comm, t->pid);
 			break;
+		case BLOCKER_TYPE_RWSEM_READER:
+		case BLOCKER_TYPE_RWSEM_WRITER:
+			pr_err("INFO: task %s:%d <%s> blocked on an rw-semaphore likely owned by task %s:%d <%s>\n",
+			       task->comm, task->pid, rwsem_blocked_as, t->comm,
+			       t->pid, rwsem_blocked_by);
+			break;
 		}
 		sched_show_task(t);
 		return;