diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c
index 5bc3498..cdf318d 100644
--- a/kernel/livepatch/transition.c
+++ b/kernel/livepatch/transition.c
@@ -1,20 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * transition.c - Kernel Live Patching transition functions
  *
  * Copyright (C) 2015-2016 Josh Poimboeuf <jpoimboe@redhat.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -29,11 +17,13 @@
 #define MAX_STACK_ENTRIES  100
 #define STACK_ERR_BUF_SIZE 128
 
+#define SIGNALS_TIMEOUT 15
+
 struct klp_patch *klp_transition_patch;
 
 static int klp_target_state = KLP_UNDEFINED;
 
-static bool klp_forced = false;
+static unsigned int klp_signals_cnt;
 
 /*
  * This work can be performed periodically to finish patching or unpatching any
@@ -52,7 +42,7 @@
 
 /*
  * This function is just a stub to implement a hard force
- * of synchronize_sched(). This requires synchronizing
+ * of synchronize_rcu(). This requires synchronizing
  * tasks even in userspace and idle.
  */
 static void klp_sync(struct work_struct *work)
@@ -87,6 +77,11 @@
 		 klp_transition_patch->mod->name,
 		 klp_target_state == KLP_PATCHED ? "patching" : "unpatching");
 
+	if (klp_transition_patch->replace && klp_target_state == KLP_PATCHED) {
+		klp_discard_replaced_patches(klp_transition_patch);
+		klp_discard_nops(klp_transition_patch);
+	}
+
 	if (klp_target_state == KLP_UNPATCHED) {
 		/*
 		 * All tasks have transitioned to KLP_UNPATCHED so we can now
@@ -136,13 +131,6 @@
 	pr_notice("'%s': %s complete\n", klp_transition_patch->mod->name,
 		  klp_target_state == KLP_PATCHED ? "patching" : "unpatching");
 
-	/*
-	 * klp_forced set implies unbounded increase of module's ref count if
-	 * the module is disabled/enabled in a loop.
-	 */
-	if (!klp_forced && klp_target_state == KLP_UNPATCHED)
-		module_put(klp_transition_patch->mod);
-
 	klp_target_state = KLP_UNDEFINED;
 	klp_transition_patch = NULL;
 }
@@ -175,7 +163,7 @@
 void klp_update_patch_state(struct task_struct *task)
 {
 	/*
-	 * A variant of synchronize_sched() is used to allow patching functions
+	 * A variant of synchronize_rcu() is used to allow patching functions
 	 * where RCU is not watching, see klp_synchronize_transition().
 	 */
 	preempt_disable_notrace();
@@ -202,15 +190,15 @@
  * Determine whether the given stack trace includes any references to a
  * to-be-patched or to-be-unpatched function.
  */
-static int klp_check_stack_func(struct klp_func *func,
-				struct stack_trace *trace)
+static int klp_check_stack_func(struct klp_func *func, unsigned long *entries,
+				unsigned int nr_entries)
 {
 	unsigned long func_addr, func_size, address;
 	struct klp_ops *ops;
 	int i;
 
-	for (i = 0; i < trace->nr_entries; i++) {
-		address = trace->entries[i];
+	for (i = 0; i < nr_entries; i++) {
+		address = entries[i];
 
 		if (klp_target_state == KLP_UNPATCHED) {
 			 /*
@@ -224,11 +212,11 @@
 			 * Check for the to-be-patched function
 			 * (the previous func).
 			 */
-			ops = klp_find_ops(func->old_addr);
+			ops = klp_find_ops(func->old_func);
 
 			if (list_is_singular(&ops->func_stack)) {
 				/* original function */
-				func_addr = func->old_addr;
+				func_addr = (unsigned long)func->old_func;
 				func_size = func->old_size;
 			} else {
 				/* previously patched function */
@@ -254,29 +242,24 @@
 static int klp_check_stack(struct task_struct *task, char *err_buf)
 {
 	static unsigned long entries[MAX_STACK_ENTRIES];
-	struct stack_trace trace;
 	struct klp_object *obj;
 	struct klp_func *func;
-	int ret;
+	int ret, nr_entries;
 
-	trace.skip = 0;
-	trace.nr_entries = 0;
-	trace.max_entries = MAX_STACK_ENTRIES;
-	trace.entries = entries;
-	ret = save_stack_trace_tsk_reliable(task, &trace);
-	WARN_ON_ONCE(ret == -ENOSYS);
-	if (ret) {
+	ret = stack_trace_save_tsk_reliable(task, entries, ARRAY_SIZE(entries));
+	if (ret < 0) {
 		snprintf(err_buf, STACK_ERR_BUF_SIZE,
 			 "%s: %s:%d has an unreliable stack\n",
 			 __func__, task->comm, task->pid);
 		return ret;
 	}
+	nr_entries = ret;
 
 	klp_for_each_object(klp_transition_patch, obj) {
 		if (!obj->patched)
 			continue;
 		klp_for_each_func(obj, func) {
-			ret = klp_check_stack_func(func, &trace);
+			ret = klp_check_stack_func(func, entries, nr_entries);
 			if (ret) {
 				snprintf(err_buf, STACK_ERR_BUF_SIZE,
 					 "%s: %s:%d is sleeping on function %s\n",
@@ -297,11 +280,11 @@
  */
 static bool klp_try_switch_task(struct task_struct *task)
 {
+	static char err_buf[STACK_ERR_BUF_SIZE];
 	struct rq *rq;
 	struct rq_flags flags;
 	int ret;
 	bool success = false;
-	char err_buf[STACK_ERR_BUF_SIZE];
 
 	err_buf[0] = '\0';
 
@@ -310,6 +293,13 @@
 		return true;
 
 	/*
+	 * For arches which don't have reliable stack traces, we have to rely
+	 * on other methods (e.g., switching tasks at kernel exit).
+	 */
+	if (!klp_have_reliable_stack())
+		return false;
+
+	/*
 	 * Now try to check the stack for any to-be-patched or to-be-unpatched
 	 * functions.  If all goes well, switch the task to the target patch
 	 * state.
@@ -344,7 +334,47 @@
 		pr_debug("%s", err_buf);
 
 	return success;
+}
 
+/*
+ * Sends a fake signal to all non-kthread tasks with TIF_PATCH_PENDING set.
+ * Kthreads with TIF_PATCH_PENDING set are woken up.
+ */
+static void klp_send_signals(void)
+{
+	struct task_struct *g, *task;
+
+	if (klp_signals_cnt == SIGNALS_TIMEOUT)
+		pr_notice("signaling remaining tasks\n");
+
+	read_lock(&tasklist_lock);
+	for_each_process_thread(g, task) {
+		if (!klp_patch_pending(task))
+			continue;
+
+		/*
+		 * There is a small race here. We could see TIF_PATCH_PENDING
+		 * set and decide to wake up a kthread or send a fake signal.
+		 * Meanwhile the task could migrate itself and the action
+		 * would be meaningless. It is not serious though.
+		 */
+		if (task->flags & PF_KTHREAD) {
+			/*
+			 * Wake up a kthread which sleeps interruptedly and
+			 * still has not been migrated.
+			 */
+			wake_up_state(task, TASK_INTERRUPTIBLE);
+		} else {
+			/*
+			 * Send fake signal to all non-kthread tasks which are
+			 * still not migrated.
+			 */
+			spin_lock_irq(&task->sighand->siglock);
+			signal_wake_up(task, 0);
+			spin_unlock_irq(&task->sighand->siglock);
+		}
+	}
+	read_unlock(&tasklist_lock);
 }
 
 /*
@@ -359,6 +389,7 @@
 {
 	unsigned int cpu;
 	struct task_struct *g, *task;
+	struct klp_patch *patch;
 	bool complete = true;
 
 	WARN_ON_ONCE(klp_target_state == KLP_UNDEFINED);
@@ -396,6 +427,10 @@
 	put_online_cpus();
 
 	if (!complete) {
+		if (klp_signals_cnt && !(klp_signals_cnt % SIGNALS_TIMEOUT))
+			klp_send_signals();
+		klp_signals_cnt++;
+
 		/*
 		 * Some tasks weren't able to be switched over.  Try again
 		 * later and/or wait for other methods like kernel exit
@@ -407,7 +442,18 @@
 	}
 
 	/* we're done, now cleanup the data structures */
+	patch = klp_transition_patch;
 	klp_complete_transition();
+
+	/*
+	 * It would make more sense to free the patch in
+	 * klp_complete_transition() but it is called also
+	 * from klp_cancel_transition().
+	 */
+	if (!patch->enabled) {
+		klp_free_patch_start(patch);
+		schedule_work(&patch->free_work);
+	}
 }
 
 /*
@@ -446,6 +492,8 @@
 		if (task->patch_state != klp_target_state)
 			set_tsk_thread_flag(task, TIF_PATCH_PENDING);
 	}
+
+	klp_signals_cnt = 0;
 }
 
 /*
@@ -569,47 +617,6 @@
 }
 
 /*
- * Sends a fake signal to all non-kthread tasks with TIF_PATCH_PENDING set.
- * Kthreads with TIF_PATCH_PENDING set are woken up. Only admin can request this
- * action currently.
- */
-void klp_send_signals(void)
-{
-	struct task_struct *g, *task;
-
-	pr_notice("signaling remaining tasks\n");
-
-	read_lock(&tasklist_lock);
-	for_each_process_thread(g, task) {
-		if (!klp_patch_pending(task))
-			continue;
-
-		/*
-		 * There is a small race here. We could see TIF_PATCH_PENDING
-		 * set and decide to wake up a kthread or send a fake signal.
-		 * Meanwhile the task could migrate itself and the action
-		 * would be meaningless. It is not serious though.
-		 */
-		if (task->flags & PF_KTHREAD) {
-			/*
-			 * Wake up a kthread which sleeps interruptedly and
-			 * still has not been migrated.
-			 */
-			wake_up_state(task, TASK_INTERRUPTIBLE);
-		} else {
-			/*
-			 * Send fake signal to all non-kthread tasks which are
-			 * still not migrated.
-			 */
-			spin_lock_irq(&task->sighand->siglock);
-			signal_wake_up(task, 0);
-			spin_unlock_irq(&task->sighand->siglock);
-		}
-	}
-	read_unlock(&tasklist_lock);
-}
-
-/*
  * Drop TIF_PATCH_PENDING of all tasks on admin's request. This forces an
  * existing transition to finish.
  *
@@ -620,6 +627,7 @@
  */
 void klp_force_transition(void)
 {
+	struct klp_patch *patch;
 	struct task_struct *g, *task;
 	unsigned int cpu;
 
@@ -633,5 +641,6 @@
 	for_each_possible_cpu(cpu)
 		klp_update_patch_state(idle_task(cpu));
 
-	klp_forced = true;
+	klp_for_each_patch(patch)
+		patch->forced = true;
 }