Merging upstream version 6.9.9.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

5 files changed, 52 insertions, 20 deletions

diff --git a/kernel/dma/map_benchmark.c b/kernel/dma/map_benchmark.c
index f7f3d14fa6..4950e0b622 100644
--- a/kernel/dma/map_benchmark.c
+++ b/kernel/dma/map_benchmark.c
@@ -256,6 +256,9 @@ static long map_benchmark_ioctl(struct file *file, unsigned int cmd,
 		 * dma_mask changed by benchmark
 		 */
 		dma_set_mask(map->dev, old_dma_mask);
+
+		if (ret)
+			return ret;
 		break;
 	default:
 		return -EINVAL;
diff --git a/kernel/exit.c b/kernel/exit.c
index 41a12630cb..2b9ef8abff 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -488,6 +488,8 @@ retry:
 	 * Search through everything else, we should not get here often.
 	 */
 	for_each_process(g) {
+		if (atomic_read(&mm->mm_users) <= 1)
+			break;
 		if (g->flags & PF_KTHREAD)
 			continue;
 		for_each_thread(g, c) {
diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c
index bc8abb8549..6e6f6071cf 100644
--- a/kernel/locking/mutex-debug.c
+++ b/kernel/locking/mutex-debug.c
@@ -12,6 +12,7 @@
  */
 #include <linux/mutex.h>
 #include <linux/delay.h>
+#include <linux/device.h>
 #include <linux/export.h>
 #include <linux/poison.h>
 #include <linux/sched.h>
@@ -89,6 +90,17 @@ void debug_mutex_init(struct mutex *lock, const char *name,
 	lock->magic = lock;
 }
 
+static void devm_mutex_release(void *res)
+{
+	mutex_destroy(res);
+}
+
+int __devm_mutex_init(struct device *dev, struct mutex *lock)
+{
+	return devm_add_action_or_reset(dev, devm_mutex_release, lock);
+}
+EXPORT_SYMBOL_GPL(__devm_mutex_init);
+
 /***
  * mutex_destroy - mark a mutex unusable
  * @lock: the mutex to be destroyed
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 5bc04bfe2d..c6f24d1786 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -1600,7 +1600,7 @@ int swsusp_check(bool exclusive)
 
 put:
 		if (error)
-			fput(hib_resume_bdev_file);
+			bdev_fput(hib_resume_bdev_file);
 		else
 			pr_debug("Image signature found, resuming\n");
 	} else {
diff --git a/kernel/vhost_task.c b/kernel/vhost_task.c
index da35e5b7f0..8800f5acc0 100644
--- a/kernel/vhost_task.c
+++ b/kernel/vhost_task.c
@@ -10,38 +10,32 @@
 
 enum vhost_task_flags {
 	VHOST_TASK_FLAGS_STOP,
+	VHOST_TASK_FLAGS_KILLED,
 };
 
 struct vhost_task {
 	bool (*fn)(void *data);
+	void (*handle_sigkill)(void *data);
 	void *data;
 	struct completion exited;
 	unsigned long flags;
 	struct task_struct *task;
+	/* serialize SIGKILL and vhost_task_stop calls */
+	struct mutex exit_mutex;
 };
 
 static int vhost_task_fn(void *data)
 {
 	struct vhost_task *vtsk = data;
-	bool dead = false;
 
 	for (;;) {
 		bool did_work;
 
-		if (!dead && signal_pending(current)) {
+		if (signal_pending(current)) {
 			struct ksignal ksig;
-			/*
-			 * Calling get_signal will block in SIGSTOP,
-			 * or clear fatal_signal_pending, but remember
-			 * what was set.
-			 *
-			 * This thread won't actually exit until all
-			 * of the file descriptors are closed, and
-			 * the release function is called.
-			 */
-			dead = get_signal(&ksig);
-			if (dead)
-				clear_thread_flag(TIF_SIGPENDING);
+
+			if (get_signal(&ksig))
+				break;
 		}
 
 		/* mb paired w/ vhost_task_stop */
@@ -57,7 +51,19 @@ static int vhost_task_fn(void *data)
 			schedule();
 	}
 
+	mutex_lock(&vtsk->exit_mutex);
+	/*
+	 * If a vhost_task_stop and SIGKILL race, we can ignore the SIGKILL.
+	 * When the vhost layer has called vhost_task_stop it's already stopped
+	 * new work and flushed.
+	 */
+	if (!test_bit(VHOST_TASK_FLAGS_STOP, &vtsk->flags)) {
+		set_bit(VHOST_TASK_FLAGS_KILLED, &vtsk->flags);
+		vtsk->handle_sigkill(vtsk->data);
+	}
+	mutex_unlock(&vtsk->exit_mutex);
 	complete(&vtsk->exited);
+
 	do_exit(0);
 }
 
@@ -78,12 +84,17 @@ EXPORT_SYMBOL_GPL(vhost_task_wake);
  * @vtsk: vhost_task to stop
  *
  * vhost_task_fn ensures the worker thread exits after
- * VHOST_TASK_FLAGS_SOP becomes true.
+ * VHOST_TASK_FLAGS_STOP becomes true.
  */
 void vhost_task_stop(struct vhost_task *vtsk)
 {
-	set_bit(VHOST_TASK_FLAGS_STOP, &vtsk->flags);
-	vhost_task_wake(vtsk);
+	mutex_lock(&vtsk->exit_mutex);
+	if (!test_bit(VHOST_TASK_FLAGS_KILLED, &vtsk->flags)) {
+		set_bit(VHOST_TASK_FLAGS_STOP, &vtsk->flags);
+		vhost_task_wake(vtsk);
+	}
+	mutex_unlock(&vtsk->exit_mutex);
+
 	/*
 	 * Make sure vhost_task_fn is no longer accessing the vhost_task before
 	 * freeing it below.
@@ -96,14 +107,16 @@ EXPORT_SYMBOL_GPL(vhost_task_stop);
 /**
  * vhost_task_create - create a copy of a task to be used by the kernel
  * @fn: vhost worker function
- * @arg: data to be passed to fn
+ * @handle_sigkill: vhost function to handle when we are killed
+ * @arg: data to be passed to fn and handled_kill
  * @name: the thread's name
  *
  * This returns a specialized task for use by the vhost layer or NULL on
  * failure. The returned task is inactive, and the caller must fire it up
  * through vhost_task_start().
  */
-struct vhost_task *vhost_task_create(bool (*fn)(void *), void *arg,
+struct vhost_task *vhost_task_create(bool (*fn)(void *),
+				     void (*handle_sigkill)(void *), void *arg,
 				     const char *name)
 {
 	struct kernel_clone_args args = {
@@ -122,8 +135,10 @@ struct vhost_task *vhost_task_create(bool (*fn)(void *), void *arg,
 	if (!vtsk)
 		return NULL;
 	init_completion(&vtsk->exited);
+	mutex_init(&vtsk->exit_mutex);
 	vtsk->data = arg;
 	vtsk->fn = fn;
+	vtsk->handle_sigkill = handle_sigkill;
 
 	args.fn_arg = vtsk;