Upgrade to 4.4.50-rt62

The current kernel is based on rt kernel v4.4.6-rt14. We will upgrade it
to 4.4.50-rt62.
The command to achieve it is:
a) Clone a git repo from
git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git

b) Get the diff between this two changesets:
git diff 640eca2901f3435e616157b11379d3223a44b391
705619beeea1b0b48219a683fd1a901a86fdaf5e

where the two commits are:
[yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only
640eca2901f3435e616157b11379d3223a44b391
640eca2901f3 v4.4.6-rt14
localversion-rt
[yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only
705619beeea1b0b48219a683fd1a901a86fdaf5e
705619beeea1 Linux 4.4.50-rt62
localversion-rt

c) One patch has been backported thus revert the patch before applying.

 filterdiff -p1 -x scripts/package/Makefile
~/tmp/v4.4.6-rt14-4.4.50-rt62.diff  |patch -p1 --dry-run

Upstream status: backport

Change-Id: I244d57a32f6066e5a5b9915f9fbf99e7bbca6e01
Signed-off-by: Yunhong Jiang <yunhong.jiang@linux.intel.com>

1 files changed, 15 insertions, 21 deletions

diff --git a/kernel/drivers/usb/gadget/function/f_mass_storage.c b/kernel/drivers/usb/gadget/function/f_mass_storage.c
index 223ccf89d..a4f664062 100644
--- a/kernel/drivers/usb/gadget/function/f_mass_storage.c
+++ b/kernel/drivers/usb/gadget/function/f_mass_storage.c
@@ -2977,25 +2977,6 @@ void fsg_common_set_inquiry_string(struct fsg_common *common, const char *vn,
 }
 EXPORT_SYMBOL_GPL(fsg_common_set_inquiry_string);
 
-int fsg_common_run_thread(struct fsg_common *common)
-{
-	common->state = FSG_STATE_IDLE;
-	/* Tell the thread to start working */
-	common->thread_task =
-		kthread_create(fsg_main_thread, common, "file-storage");
-	if (IS_ERR(common->thread_task)) {
-		common->state = FSG_STATE_TERMINATED;
-		return PTR_ERR(common->thread_task);
-	}
-
-	DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
-
-	wake_up_process(common->thread_task);
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(fsg_common_run_thread);
-
 static void fsg_common_release(struct kref *ref)
 {
 	struct fsg_common *common = container_of(ref, struct fsg_common, ref);
@@ -3005,6 +2986,7 @@ static void fsg_common_release(struct kref *ref)
 	if (common->state != FSG_STATE_TERMINATED) {
 		raise_exception(common, FSG_STATE_EXIT);
 		wait_for_completion(&common->thread_notifier);
+		common->thread_task = NULL;
 	}
 
 	for (i = 0; i < ARRAY_SIZE(common->luns); ++i) {
@@ -3050,9 +3032,21 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
 		if (ret)
 			return ret;
 		fsg_common_set_inquiry_string(fsg->common, NULL, NULL);
-		ret = fsg_common_run_thread(fsg->common);
-		if (ret)
+	}
+
+	if (!common->thread_task) {
+		common->state = FSG_STATE_IDLE;
+		common->thread_task =
+			kthread_create(fsg_main_thread, common, "file-storage");
+		if (IS_ERR(common->thread_task)) {
+			int ret = PTR_ERR(common->thread_task);
+			common->thread_task = NULL;
+			common->state = FSG_STATE_TERMINATED;
 			return ret;
+		}
+		DBG(common, "I/O thread pid: %d\n",
+		    task_pid_nr(common->thread_task));
+		wake_up_process(common->thread_task);
 	}
 
 	fsg->gadget = gadget;