Runtime verifier updates for v6.19:

- Adapt the ftracetest script to be run from a different folder
 
   This uses the already existing OPT_TEST_DIR but extends it further to run
   independent tests, then add an --rv flag to allow using the script for
   testing RV (mostly) independently on ftrace.
 
 - Add basic RV selftests in selftests/verification for more validations
 
   Add more validations for available/enabled monitors and reactors. This
   could have caught the bug introducing kernel panic solved above. Tests use
   ftracetest.
 
 - Convert react() function in reactor to use va_list directly
 
   Use a central helper to handle the variadic arguments. Clean up macros
   and mark functions as static.
 
 - Add lockdep annotations to reactors to have lockdep complain of errors
 
   If the reactors are called from improper context. Useful to develop new
   reactors. This highlights a warning in the panic reactor that is related
   to the printk subsystem and not to RV.
 
 - Convert core RV code to use lock guards and __free helpers
 
   This completely removes goto statements.
 
 - Fix compilation if !CONFIG_RV_REACTORS
 
   Fix the warning by keeping LTL monitor variable as always static.
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 -----END PGP SIGNATURE-----

Merge tag 'trace-rv-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull runtime verifier updates from Steven Rostedt:

 - Adapt the ftracetest script to be run from a different folder

   This uses the already existing OPT_TEST_DIR but extends it further to
   run independent tests, then add an --rv flag to allow using the
   script for testing RV (mostly) independently on ftrace.

 - Add basic RV selftests in selftests/verification for more validations

   Add more validations for available/enabled monitors and reactors.
   This could have caught the bug introducing kernel panic solved above.
   Tests use ftracetest.

 - Convert react() function in reactor to use va_list directly

   Use a central helper to handle the variadic arguments. Clean up
   macros and mark functions as static.

 - Add lockdep annotations to reactors to have lockdep complain of
   errors

   If the reactors are called from improper context. Useful to develop
   new reactors. This highlights a warning in the panic reactor that is
   related to the printk subsystem and not to RV.

 - Convert core RV code to use lock guards and __free helpers

   This completely removes goto statements.

 - Fix compilation if !CONFIG_RV_REACTORS

   Fix the warning by keeping LTL monitor variable as always static.

* tag 'trace-rv-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  rv: Fix compilation if !CONFIG_RV_REACTORS
  rv: Convert to use __free
  rv: Convert to use lock guard
  rv: Add explicit lockdep context for reactors
  rv: Make rv_reacting_on() static
  rv: Pass va_list to reactors
  selftests/verification: Add initial RV tests
  selftest/ftrace: Generalise ftracetest to use with RV

MAINTAINERS

@@ -22700,6 +22700,7 @@ F:	Documentation/trace/rv/
 F:	include/linux/rv.h
 F:	include/rv/
 F:	kernel/trace/rv/
+F:	tools/testing/selftests/verification/
 F:	tools/verification/
 
 RUST

include/linux/rv.h

@@ -88,7 +88,7 @@ union rv_task_monitor {
 struct rv_reactor {
 	const char		*name;
 	const char		*description;
-	__printf(1, 2) void	(*react)(const char *msg, ...);
+	__printf(1, 0) void	(*react)(const char *msg, va_list args);
 	struct list_head	list;
 };
 #endif
@@ -102,7 +102,7 @@ struct rv_monitor {
 	void			(*reset)(void);
 #ifdef CONFIG_RV_REACTORS
 	struct rv_reactor	*reactor;
-	__printf(1, 2) void	(*react)(const char *msg, ...);
+	__printf(1, 0) void	(*react)(const char *msg, va_list args);
 #endif
 	struct list_head	list;
 	struct rv_monitor	*parent;
@@ -116,13 +116,14 @@ int rv_get_task_monitor_slot(void);
 void rv_put_task_monitor_slot(int slot);
 
 #ifdef CONFIG_RV_REACTORS
-bool rv_reacting_on(void);
 int rv_unregister_reactor(struct rv_reactor *reactor);
 int rv_register_reactor(struct rv_reactor *reactor);
+__printf(2, 3)
+void rv_react(struct rv_monitor *monitor, const char *msg, ...);
 #else
-static inline bool rv_reacting_on(void)
+__printf(2, 3)
+static inline void rv_react(struct rv_monitor *monitor, const char *msg, ...)
 {
-	return false;
 }
 #endif /* CONFIG_RV_REACTORS */
 

include/rv/da_monitor.h

@@ -16,34 +16,19 @@
 #include <linux/bug.h>
 #include <linux/sched.h>
 
-#ifdef CONFIG_RV_REACTORS
-
-#define DECLARE_RV_REACTING_HELPERS(name, type)							\
-static void cond_react_##name(type curr_state, type event)					\
-{												\
-	if (!rv_reacting_on() || !rv_##name.react)						\
-		return;										\
-	rv_##name.react("rv: monitor %s does not allow event %s on state %s\n",			\
-			#name,									\
-			model_get_event_name_##name(event),					\
-			model_get_state_name_##name(curr_state));				\
-}
-
-#else /* CONFIG_RV_REACTOR */
-
-#define DECLARE_RV_REACTING_HELPERS(name, type)							\
-static void cond_react_##name(type curr_state, type event)					\
-{												\
-	return;											\
-}
-#endif
-
 /*
  * Generic helpers for all types of deterministic automata monitors.
  */
 #define DECLARE_DA_MON_GENERIC_HELPERS(name, type)						\
 												\
-DECLARE_RV_REACTING_HELPERS(name, type)								\
+static void react_##name(type curr_state, type event)						\
+{												\
+	rv_react(&rv_##name,									\
+		 "rv: monitor %s does not allow event %s on state %s\n",			\
+		 #name,										\
+		 model_get_event_name_##name(event),						\
+		 model_get_state_name_##name(curr_state));					\
+}												\
 												\
 /*												\
  * da_monitor_reset_##name - reset a monitor and setting it to init state			\
@@ -126,7 +111,7 @@ da_event_##name(struct da_monitor *da_mon, enum events_##name event)				\
 	for (int i = 0; i < MAX_DA_RETRY_RACING_EVENTS; i++) {					\
 		next_state = model_get_next_state_##name(curr_state, event);			\
 		if (next_state == INVALID_STATE) {						\
-			cond_react_##name(curr_state, event);					\
+			react_##name(curr_state, event);					\
 			trace_error_##name(model_get_state_name_##name(curr_state),		\
 					   model_get_event_name_##name(event));			\
 			return false;								\
@@ -165,7 +150,7 @@ static inline bool da_event_##name(struct da_monitor *da_mon, struct task_struct
 	for (int i = 0; i < MAX_DA_RETRY_RACING_EVENTS; i++) {					\
 		next_state = model_get_next_state_##name(curr_state, event);			\
 		if (next_state == INVALID_STATE) {						\
-			cond_react_##name(curr_state, event);					\
+			react_##name(curr_state, event);					\
 			trace_error_##name(tsk->pid,						\
 					   model_get_state_name_##name(curr_state),		\
 					   model_get_event_name_##name(event));			\

include/rv/ltl_monitor.h

@@ -16,23 +16,9 @@
 #error "Please include $(MODEL_NAME).h generated by rvgen"
 #endif
 
-#ifdef CONFIG_RV_REACTORS
 #define RV_MONITOR_NAME CONCATENATE(rv_, MONITOR_NAME)
 static struct rv_monitor RV_MONITOR_NAME;
 
-static void rv_cond_react(struct task_struct *task)
-{
-	if (!rv_reacting_on() || !RV_MONITOR_NAME.react)
-		return;
-	RV_MONITOR_NAME.react("rv: "__stringify(MONITOR_NAME)": %s[%d]: violation detected\n",
-			      task->comm, task->pid);
-}
-#else
-static void rv_cond_react(struct task_struct *task)
-{
-}
-#endif
-
 static int ltl_monitor_slot = RV_PER_TASK_MONITOR_INIT;
 
 static void ltl_atoms_fetch(struct task_struct *task, struct ltl_monitor *mon);
@@ -98,7 +84,8 @@ static void ltl_monitor_destroy(void)
 static void ltl_illegal_state(struct task_struct *task, struct ltl_monitor *mon)
 {
 	CONCATENATE(trace_error_, MONITOR_NAME)(task);
-	rv_cond_react(task);
+	rv_react(&RV_MONITOR_NAME, "rv: "__stringify(MONITOR_NAME)": %s[%d]: violation detected\n",
+		 task->comm, task->pid);
 }
 
 static void ltl_attempt_start(struct task_struct *task, struct ltl_monitor *mon)

kernel/trace/rv/reactor_panic.c

@@ -13,13 +13,9 @@
 #include <linux/init.h>
 #include <linux/rv.h>
 
-__printf(1, 2) static void rv_panic_reaction(const char *msg, ...)
+__printf(1, 0) static void rv_panic_reaction(const char *msg, va_list args)
 {
-	va_list args;
-
-	va_start(args, msg);
 	vpanic(msg, args);
-	va_end(args);
 }
 
 static struct rv_reactor rv_panic = {

kernel/trace/rv/reactor_printk.c

@@ -12,13 +12,9 @@
 #include <linux/init.h>
 #include <linux/rv.h>
 
-__printf(1, 2) static void rv_printk_reaction(const char *msg, ...)
+__printf(1, 0) static void rv_printk_reaction(const char *msg, va_list args)
 {
-	va_list args;
-
-	va_start(args, msg);
 	vprintk_deferred(msg, args);
-	va_end(args);
 }
 
 static struct rv_reactor rv_printk = {

kernel/trace/rv/rv.c

@@ -375,15 +375,13 @@ static ssize_t monitor_enable_write_data(struct file *filp, const char __user *u
 	if (retval)
 		return retval;
 
-	mutex_lock(&rv_interface_lock);
+	guard(mutex)(&rv_interface_lock);
 
 	if (val)
 		retval = rv_enable_monitor(mon);
 	else
 		retval = rv_disable_monitor(mon);
 
-	mutex_unlock(&rv_interface_lock);
-
 	return retval ? : count;
 }
 
@@ -422,35 +420,27 @@ static const struct file_operations interface_desc_fops = {
 static int create_monitor_dir(struct rv_monitor *mon, struct rv_monitor *parent)
 {
 	struct dentry *root = parent ? parent->root_d : get_monitors_root();
-	const char *name = mon->name;
+	struct dentry *dir __free(rv_remove) = rv_create_dir(mon->name, root);
 	struct dentry *tmp;
 	int retval;
 
-	mon->root_d = rv_create_dir(name, root);
+	if (!dir)
-	if (!mon->root_d)
 		return -ENOMEM;
 
-	tmp = rv_create_file("enable", RV_MODE_WRITE, mon->root_d, mon, &interface_enable_fops);
+	tmp = rv_create_file("enable", RV_MODE_WRITE, dir, mon, &interface_enable_fops);
-	if (!tmp) {
+	if (!tmp)
-		retval = -ENOMEM;
+		return -ENOMEM;
-		goto out_remove_root;
-	}
 
-	tmp = rv_create_file("desc", RV_MODE_READ, mon->root_d, mon, &interface_desc_fops);
+	tmp = rv_create_file("desc", RV_MODE_READ, dir, mon, &interface_desc_fops);
-	if (!tmp) {
+	if (!tmp)
-		retval = -ENOMEM;
+		return -ENOMEM;
-		goto out_remove_root;
-	}
 
-	retval = reactor_populate_monitor(mon);
+	retval = reactor_populate_monitor(mon, dir);
 	if (retval)
-		goto out_remove_root;
+		return retval;
 
+	mon->root_d = no_free_ptr(dir);
 	return 0;
-
-out_remove_root:
-	rv_remove(mon->root_d);
-	return retval;
 }
 
 /*
@@ -568,7 +558,7 @@ static void disable_all_monitors(void)
 	struct rv_monitor *mon;
 	int enabled = 0;
 
-	mutex_lock(&rv_interface_lock);
+	guard(mutex)(&rv_interface_lock);
 
 	list_for_each_entry(mon, &rv_monitors_list, list)
 		enabled += __rv_disable_monitor(mon, false);
@@ -581,8 +571,6 @@ static void disable_all_monitors(void)
 		 */
 		tracepoint_synchronize_unregister();
 	}
-
-	mutex_unlock(&rv_interface_lock);
 }
 
 static int enabled_monitors_open(struct inode *inode, struct file *file)
@@ -623,7 +611,7 @@ static ssize_t enabled_monitors_write(struct file *filp, const char __user *user
 	if (!len)
 		return count;
 
-	mutex_lock(&rv_interface_lock);
+	guard(mutex)(&rv_interface_lock);
 
 	retval = -EINVAL;
 
@@ -644,13 +632,11 @@ static ssize_t enabled_monitors_write(struct file *filp, const char __user *user
 		else
 			retval = rv_disable_monitor(mon);
 
-		if (!retval)
+		if (retval)
-			retval = count;
+			return retval;
-
+		return count;
-		break;
 	}
 
-	mutex_unlock(&rv_interface_lock);
 	return retval;
 }
 
@@ -737,7 +723,7 @@ static ssize_t monitoring_on_write_data(struct file *filp, const char __user *us
 	if (retval)
 		return retval;
 
-	mutex_lock(&rv_interface_lock);
+	guard(mutex)(&rv_interface_lock);
 
 	if (val)
 		turn_monitoring_on_with_reset();
@@ -750,8 +736,6 @@ static ssize_t monitoring_on_write_data(struct file *filp, const char __user *us
 	 */
 	tracepoint_synchronize_unregister();
 
-	mutex_unlock(&rv_interface_lock);
-
 	return count;
 }
 
@@ -784,28 +768,26 @@ int rv_register_monitor(struct rv_monitor *monitor, struct rv_monitor *parent)
 		return -EINVAL;
 	}
 
-	mutex_lock(&rv_interface_lock);
+	guard(mutex)(&rv_interface_lock);
 
 	list_for_each_entry(r, &rv_monitors_list, list) {
 		if (strcmp(monitor->name, r->name) == 0) {
 			pr_info("Monitor %s is already registered\n", monitor->name);
-			retval = -EEXIST;
+			return -EEXIST;
-			goto out_unlock;
 		}
 	}
 
 	if (parent && rv_is_nested_monitor(parent)) {
 		pr_info("Parent monitor %s is already nested, cannot nest further\n",
 			parent->name);
-		retval = -EINVAL;
+		return -EINVAL;
-		goto out_unlock;
 	}
 
 	monitor->parent = parent;
 
 	retval = create_monitor_dir(monitor, parent);
 	if (retval)
-		goto out_unlock;
+		return retval;
 
 	/* keep children close to the parent for easier visualisation */
 	if (parent)
@@ -813,9 +795,7 @@ int rv_register_monitor(struct rv_monitor *monitor, struct rv_monitor *parent)
 	else
 		list_add_tail(&monitor->list, &rv_monitors_list);
 
-out_unlock:
+	return 0;
-	mutex_unlock(&rv_interface_lock);
-	return retval;
 }
 
 /**
@@ -826,13 +806,12 @@ int rv_register_monitor(struct rv_monitor *monitor, struct rv_monitor *parent)
  */
 int rv_unregister_monitor(struct rv_monitor *monitor)
 {
-	mutex_lock(&rv_interface_lock);
+	guard(mutex)(&rv_interface_lock);
 
 	rv_disable_monitor(monitor);
 	list_del(&monitor->list);
 	destroy_monitor_dir(monitor);
 
-	mutex_unlock(&rv_interface_lock);
 	return 0;
 }
 
@@ -840,39 +819,36 @@ int __init rv_init_interface(void)
 {
 	struct dentry *tmp;
 	int retval;
+	struct dentry *root_dir __free(rv_remove) = rv_create_dir("rv", NULL);
 
-	rv_root.root_dir = rv_create_dir("rv", NULL);
+	if (!root_dir)
-	if (!rv_root.root_dir)
+		return 1;
-		goto out_err;
 
-	rv_root.monitors_dir = rv_create_dir("monitors", rv_root.root_dir);
+	rv_root.monitors_dir = rv_create_dir("monitors", root_dir);
 	if (!rv_root.monitors_dir)
-		goto out_err;
+		return 1;
 
-	tmp = rv_create_file("available_monitors", RV_MODE_READ, rv_root.root_dir, NULL,
+	tmp = rv_create_file("available_monitors", RV_MODE_READ, root_dir, NULL,
 			     &available_monitors_ops);
 	if (!tmp)
-		goto out_err;
+		return 1;
 
-	tmp = rv_create_file("enabled_monitors", RV_MODE_WRITE, rv_root.root_dir, NULL,
+	tmp = rv_create_file("enabled_monitors", RV_MODE_WRITE, root_dir, NULL,
 			     &enabled_monitors_ops);
 	if (!tmp)
-		goto out_err;
+		return 1;
 
-	tmp = rv_create_file("monitoring_on", RV_MODE_WRITE, rv_root.root_dir, NULL,
+	tmp = rv_create_file("monitoring_on", RV_MODE_WRITE, root_dir, NULL,
 			     &monitoring_on_fops);
 	if (!tmp)
-		goto out_err;
+		return 1;
-	retval = init_rv_reactors(rv_root.root_dir);
+	retval = init_rv_reactors(root_dir);
 	if (retval)
-		goto out_err;
+		return 1;
 
 	turn_monitoring_on();
 
-	return 0;
+	rv_root.root_dir = no_free_ptr(root_dir);
 
-out_err:
+	return 0;
-	rv_remove(rv_root.root_dir);
-	printk(KERN_ERR "RV: Error while creating the RV interface\n");
-	return 1;
 }

kernel/trace/rv/rv.h

@@ -17,6 +17,8 @@ struct rv_interface {
 #define rv_create_file			tracefs_create_file
 #define rv_remove			tracefs_remove
 
+DEFINE_FREE(rv_remove, struct dentry *, if (_T) rv_remove(_T));
+
 #define MAX_RV_MONITOR_NAME_SIZE	32
 #define MAX_RV_REACTOR_NAME_SIZE	32
 
@@ -30,10 +32,10 @@ bool rv_is_container_monitor(struct rv_monitor *mon);
 bool rv_is_nested_monitor(struct rv_monitor *mon);
 
 #ifdef CONFIG_RV_REACTORS
-int reactor_populate_monitor(struct rv_monitor *mon);
+int reactor_populate_monitor(struct rv_monitor *mon, struct dentry *root);
 int init_rv_reactors(struct dentry *root_dir);
 #else
-static inline int reactor_populate_monitor(struct rv_monitor *mon)
+static inline int reactor_populate_monitor(struct rv_monitor *mon, struct dentry *root)
 {
 	return 0;
 }

kernel/trace/rv/rv_reactors.c

@@ -61,6 +61,7 @@
  *      printk
  */
 
+#include <linux/lockdep.h>
 #include <linux/slab.h>
 
 #include "rv.h"
@@ -232,9 +233,7 @@ monitor_reactors_write(struct file *file, const char __user *user_buf,
 	seq_f = file->private_data;
 	mon = seq_f->private;
 
-	mutex_lock(&rv_interface_lock);
+	guard(mutex)(&rv_interface_lock);
-
-	retval = -EINVAL;
 
 	list_for_each_entry(reactor, &rv_reactors_list, list) {
 		if (strcmp(ptr, reactor->name) != 0)
@@ -242,13 +241,10 @@ monitor_reactors_write(struct file *file, const char __user *user_buf,
 
 		monitor_swap_reactors(mon, reactor);
 
-		retval = count;
+		return count;
-		break;
 	}
 
-	mutex_unlock(&rv_interface_lock);
+	return -EINVAL;
-
-	return retval;
 }
 
 /*
@@ -309,18 +305,14 @@ static int __rv_register_reactor(struct rv_reactor *reactor)
  */
 int rv_register_reactor(struct rv_reactor *reactor)
 {
-	int retval = 0;
-
 	if (strlen(reactor->name) >= MAX_RV_REACTOR_NAME_SIZE) {
 		pr_info("Reactor %s has a name longer than %d\n",
 			reactor->name, MAX_RV_MONITOR_NAME_SIZE);
 		return -EINVAL;
 	}
 
-	mutex_lock(&rv_interface_lock);
+	guard(mutex)(&rv_interface_lock);
-	retval = __rv_register_reactor(reactor);
+	return __rv_register_reactor(reactor);
-	mutex_unlock(&rv_interface_lock);
-	return retval;
 }
 
 /**
@@ -331,9 +323,8 @@ int rv_register_reactor(struct rv_reactor *reactor)
  */
 int rv_unregister_reactor(struct rv_reactor *reactor)
 {
-	mutex_lock(&rv_interface_lock);
+	guard(mutex)(&rv_interface_lock);
 	list_del(&reactor->list);
-	mutex_unlock(&rv_interface_lock);
 	return 0;
 }
 
@@ -347,7 +338,7 @@ static bool __read_mostly reacting_on;
  *
  * Returns 1 if on, 0 otherwise.
  */
-bool rv_reacting_on(void)
+static bool rv_reacting_on(void)
 {
 	/* Ensures that concurrent monitors read consistent reacting_on */
 	smp_rmb();
@@ -389,7 +380,7 @@ static ssize_t reacting_on_write_data(struct file *filp, const char __user *user
 	if (retval)
 		return retval;
 
-	mutex_lock(&rv_interface_lock);
+	guard(mutex)(&rv_interface_lock);
 
 	if (val)
 		turn_reacting_on();
@@ -402,8 +393,6 @@ static ssize_t reacting_on_write_data(struct file *filp, const char __user *user
 	 */
 	tracepoint_synchronize_unregister();
 
-	mutex_unlock(&rv_interface_lock);
-
 	return count;
 }
 
@@ -416,14 +405,15 @@ static const struct file_operations reacting_on_fops = {
 /**
  * reactor_populate_monitor - creates per monitor reactors file
  * @mon:	The monitor.
+ * @root:	The directory of the monitor.
  *
  * Returns 0 if successful, error otherwise.
  */
-int reactor_populate_monitor(struct rv_monitor *mon)
+int reactor_populate_monitor(struct rv_monitor *mon, struct dentry *root)
 {
 	struct dentry *tmp;
 
-	tmp = rv_create_file("reactors", RV_MODE_WRITE, mon->root_d, mon, &monitor_reactors_ops);
+	tmp = rv_create_file("reactors", RV_MODE_WRITE, root, mon, &monitor_reactors_ops);
 	if (!tmp)
 		return -ENOMEM;
 
@@ -438,7 +428,7 @@ int reactor_populate_monitor(struct rv_monitor *mon)
 /*
  * Nop reactor register
  */
-__printf(1, 2) static void rv_nop_reaction(const char *msg, ...)
+__printf(1, 0) static void rv_nop_reaction(const char *msg, va_list args)
 {
 }
 
@@ -450,30 +440,42 @@ static struct rv_reactor rv_nop = {
 
 int init_rv_reactors(struct dentry *root_dir)
 {
-	struct dentry *available, *reacting;
 	int retval;
 
-	available = rv_create_file("available_reactors", RV_MODE_READ, root_dir, NULL,
+	struct dentry *available __free(rv_remove) =
-				   &available_reactors_ops);
+		rv_create_file("available_reactors", RV_MODE_READ, root_dir,
-	if (!available)
+				NULL, &available_reactors_ops);
-		goto out_err;
 
-	reacting = rv_create_file("reacting_on", RV_MODE_WRITE, root_dir, NULL, &reacting_on_fops);
+	struct dentry *reacting __free(rv_remove) =
-	if (!reacting)
+		rv_create_file("reacting_on", RV_MODE_WRITE, root_dir, NULL, &reacting_on_fops);
-		goto rm_available;
+
+	if (!reacting || !available)
+		return -ENOMEM;
 
 	retval = __rv_register_reactor(&rv_nop);
 	if (retval)
-		goto rm_reacting;
+		return retval;
 
 	turn_reacting_on();
 
+	retain_and_null_ptr(available);
+	retain_and_null_ptr(reacting);
 	return 0;
-
+}
-rm_reacting:
+
-	rv_remove(reacting);
+void rv_react(struct rv_monitor *monitor, const char *msg, ...)
-rm_available:
+{
-	rv_remove(available);
+	static DEFINE_WAIT_OVERRIDE_MAP(rv_react_map, LD_WAIT_FREE);
-out_err:
+	va_list args;
-	return -ENOMEM;
+
+	if (!rv_reacting_on() || !monitor->react)
+		return;
+
+	va_start(args, msg);
+
+	lock_map_acquire_try(&rv_react_map);
+	monitor->react(msg, args);
+	lock_map_release(&rv_react_map);
+
+	va_end(args);
 }

kernel/trace/trace.c

@@ -10969,7 +10969,8 @@ static __init int tracer_init_tracefs(void)
 		tracer_init_tracefs_work_func(NULL);
 	}
 
-	rv_init_interface();
+	if (rv_init_interface())
+		pr_err("RV: Error while creating the RV interface\n");
 
 	return 0;
 }

tools/testing/selftests/ftrace/ftracetest

@@ -22,6 +22,7 @@ echo "		--fail-unresolved Treat UNRESOLVED as a failure"
 echo "		-d|--debug Debug mode (trace all shell commands)"
 echo "		-l|--logdir <dir> Save logs on the <dir>"
 echo "		            If <dir> is -, all logs output in console only"
+echo "		--rv       Run RV selftests instead of ftrace ones"
 exit $1
 }
 
@@ -133,6 +134,10 @@ parse_opts() { # opts
       LINK_PTR=
       shift 2
     ;;
+    --rv)
+      RV_TEST=1
+      shift 1
+    ;;
     *.tc)
       if [ -f "$1" ]; then
         OPT_TEST_CASES="$OPT_TEST_CASES `abspath $1`"
@@ -152,9 +157,13 @@ parse_opts() { # opts
     ;;
     esac
   done
-  if [ ! -z "$OPT_TEST_CASES" ]; then
+  if [ -n "$OPT_TEST_CASES" ]; then
     TEST_CASES=$OPT_TEST_CASES
   fi
+  if [ -n "$OPT_TEST_DIR" -a -f "$OPT_TEST_DIR"/test.d/functions ]; then
+    TOP_DIR=$OPT_TEST_DIR
+    TEST_DIR=$TOP_DIR/test.d
+  fi
 }
 
 # Parameters
@@ -190,10 +199,6 @@ fi
 TOP_DIR=`absdir $0`
 TEST_DIR=$TOP_DIR/test.d
 TEST_CASES=`find_testcases $TEST_DIR`
-LOG_TOP_DIR=$TOP_DIR/logs
-LOG_DATE=`date +%Y%m%d-%H%M%S`
-LOG_DIR=$LOG_TOP_DIR/$LOG_DATE/
-LINK_PTR=$LOG_TOP_DIR/latest
 KEEP_LOG=0
 KTAP=0
 DEBUG=0
@@ -201,14 +206,23 @@ VERBOSE=0
 UNSUPPORTED_RESULT=0
 UNRESOLVED_RESULT=0
 STOP_FAILURE=0
+RV_TEST=0
 # Parse command-line options
 parse_opts $*
 
+LOG_TOP_DIR=$TOP_DIR/logs
+LOG_DATE=`date +%Y%m%d-%H%M%S`
+LOG_DIR=$LOG_TOP_DIR/$LOG_DATE/
+LINK_PTR=$LOG_TOP_DIR/latest
+
 [ $DEBUG -ne 0 ] && set -x
 
-# Verify parameters
+if [ $RV_TEST -ne 0 ]; then
-if [ -z "$TRACING_DIR" -o ! -d "$TRACING_DIR" ]; then
+	TRACING_DIR=$TRACING_DIR/rv
-  errexit "No ftrace directory found"
+	if [ ! -d "$TRACING_DIR" ]; then
+		err_ret=$err_skip
+		errexit "rv is not configured in this kernel"
+	fi
 fi
 
 # Preparing logs
@@ -419,7 +433,7 @@ trap 'SIG_RESULT=$XFAIL' $SIG_XFAIL
 __run_test() { # testfile
   # setup PID and PPID, $$ is not updated.
   (cd $TRACING_DIR; read PID _ < /proc/self/stat; set -e; set -x;
-   checkreq $1; initialize_ftrace; . $1)
+   checkreq $1; initialize_system; . $1)
   [ $? -ne 0 ] && kill -s $SIG_FAIL $SIG_PID
 }
 
@@ -496,7 +510,7 @@ for t in $TEST_CASES; do
     exit 1
   fi
 done
-(cd $TRACING_DIR; finish_ftrace) # for cleanup
+(cd $TRACING_DIR; finish_system) # for cleanup
 
 prlog ""
 prlog "# of passed: " `echo $PASSED_CASES | wc -w`

tools/testing/selftests/ftrace/test.d/00basic/mount_options.tc

@@ -28,7 +28,7 @@ unmount_tracefs() {
 	local mount_point="$1"
 
 	# Need to make sure the mount isn't busy so that we can umount it
-	(cd $mount_point; finish_ftrace;)
+	(cd $mount_point; finish_system;)
 
 	cleanup
 }

tools/testing/selftests/ftrace/test.d/functions

@@ -104,7 +104,7 @@ clear_dynamic_events() { # reset all current dynamic events
     done
 }
 
-initialize_ftrace() { # Reset ftrace to initial-state
+initialize_system() { # Reset ftrace to initial-state
 # As the initial state, ftrace will be set to nop tracer,
 # no events, no triggers, no filters, no function filters,
 # no probes, and tracing on.
@@ -134,8 +134,8 @@ initialize_ftrace() { # Reset ftrace to initial-state
     enable_tracing
 }
 
-finish_ftrace() {
+finish_system() {
-    initialize_ftrace
+    initialize_system
 # And recover it to default.
     [ -f options/pause-on-trace ] && echo 0 > options/pause-on-trace
 }

tools/testing/selftests/verification/.gitignore

@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+logs

tools/testing/selftests/verification/Makefile

@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0
+all:
+
+TEST_PROGS := verificationtest-ktap
+TEST_FILES := test.d settings
+EXTRA_CLEAN := $(OUTPUT)/logs/*
+
+include ../lib.mk

tools/testing/selftests/verification/config

@@ -0,0 +1 @@
+CONFIG_RV=y

tools/testing/selftests/verification/settings

@@ -0,0 +1 @@
+timeout=0

tools/testing/selftests/verification/test.d/functions

@@ -0,0 +1,39 @@
+check_requires() { # Check required files, monitors and reactors
+	for i in "$@" ; do
+		p=${i%:program}
+		m=${i%:monitor}
+		r=${i%:reactor}
+		if [ $p != $i ]; then
+			if ! which $p ; then
+				echo "Required program $p is not found."
+				exit_unresolved
+			fi
+		elif [ $m != $i ]; then
+			if ! grep -wq $m available_monitors ; then
+				echo "Required monitor $m is not configured."
+				exit_unsupported
+			fi
+		elif [ $r != $i ]; then
+			if ! grep -wq $r available_reactors ; then
+				echo "Required reactor $r is not configured."
+				exit_unsupported
+			fi
+		elif [ ! -e $i ]; then
+			echo "Required feature interface $i doesn't exist."
+			exit_unsupported
+		fi
+	done
+}
+
+initialize_system() { # Reset RV to initial-state
+	echo > enabled_monitors
+	for m in monitors/*; do
+		echo nop > $m/reactors || true
+	done
+	echo 1 > monitoring_on
+	echo 1 > reacting_on || true
+}
+
+finish_system() {
+	initialize_system
+}

tools/testing/selftests/verification/test.d/rv_monitor_enable_disable.tc

@@ -0,0 +1,75 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-or-later
+# description: Test monitor enable/disable
+
+test_simple_monitor() {
+    local monitor="$1"
+    local prefix="$2" # nested monitors
+
+    echo 1 > "monitors/$prefix$monitor/enable"
+    grep -q "$monitor$" enabled_monitors
+
+    echo 0 > "monitors/$prefix$monitor/enable"
+    ! grep -q "$monitor$" enabled_monitors
+
+    echo "$monitor" >> enabled_monitors
+    grep -q 1 "monitors/$prefix$monitor/enable"
+
+    echo "!$monitor" >> enabled_monitors
+    grep -q 0 "monitors/$prefix$monitor/enable"
+}
+
+test_container_monitor() {
+    local monitor="$1"
+	local nested
+
+    echo 1 > "monitors/$monitor/enable"
+    grep -q "^$monitor$" enabled_monitors
+
+    for nested_dir in "monitors/$monitor"/*; do
+        [ -d "$nested_dir" ] || continue
+        nested=$(basename "$nested_dir")
+        grep -q "^$monitor:$nested$" enabled_monitors
+    done
+	test -n "$nested"
+
+    echo 0 > "monitors/$monitor/enable"
+    ! grep -q "^$monitor$" enabled_monitors
+
+    for nested_dir in "monitors/$monitor"/*; do
+        [ -d "$nested_dir" ] || continue
+        nested=$(basename "$nested_dir")
+        ! grep -q "^$monitor:$nested$" enabled_monitors
+    done
+
+    echo "$monitor" >> enabled_monitors
+    grep -q 1 "monitors/$monitor/enable"
+
+    for nested_dir in "monitors/$monitor"/*; do
+        [ -d "$nested_dir" ] || continue
+        nested=$(basename "$nested_dir")
+        grep -q "^$monitor:$nested$" enabled_monitors
+    done
+
+    echo "!$monitor" >> enabled_monitors
+    grep -q 0 "monitors/$monitor/enable"
+
+    for nested_dir in "monitors/$monitor"/*; do
+        [ -d "$nested_dir" ] || continue
+        nested=$(basename "$nested_dir")
+		test_simple_monitor "$nested" "$monitor/"
+    done
+}
+
+for monitor_dir in monitors/*; do
+    monitor=$(basename "$monitor_dir")
+
+    if find "$monitor_dir" -mindepth 1 -type d | grep -q .; then
+        test_container_monitor "$monitor"
+    else
+        test_simple_monitor "$monitor"
+    fi
+done
+
+! echo non_existent_monitor > enabled_monitors
+! grep -q "^non_existent_monitor$" enabled_monitors

tools/testing/selftests/verification/test.d/rv_monitor_reactor.tc

@@ -0,0 +1,68 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-or-later
+# description: Test monitor reactor setting
+# requires: available_reactors
+
+test_monitor_reactor() {
+    local monitor="$1"
+    local prefix="$2" # nested monitors
+
+    while read -r reactor; do
+        [ "$reactor" = nop ] && continue
+
+        echo "$reactor" > "monitors/$prefix$monitor/reactors"
+        grep -q "\\[$reactor\\]" "monitors/$prefix$monitor/reactors"
+    done < available_reactors
+
+    echo nop > "monitors/$prefix$monitor/reactors"
+    grep -q "\\[nop\\]" "monitors/$prefix$monitor/reactors"
+}
+
+test_container_monitor() {
+    local monitor="$1"
+	local nested
+
+    while read -r reactor; do
+        [ "$reactor" = nop ] && continue
+
+        echo "$reactor" > "monitors/$monitor/reactors"
+        grep -q "\\[$reactor\\]" "monitors/$monitor/reactors"
+
+        for nested_dir in "monitors/$monitor"/*; do
+            [ -d "$nested_dir" ] || continue
+            nested=$(basename "$nested_dir")
+            grep -q "\\[$reactor\\]" "monitors/$monitor/$nested/reactors"
+        done
+    done < available_reactors
+	test -n "$nested"
+
+    echo nop > "monitors/$monitor/reactors"
+    grep -q "\\[nop\\]" "monitors/$monitor/reactors"
+
+    for nested_dir in "monitors/$monitor"/*; do
+        [ -d "$nested_dir" ] || continue
+        nested=$(basename "$nested_dir")
+        grep -q "\\[nop\\]" "monitors/$monitor/$nested/reactors"
+    done
+
+    for nested_dir in "monitors/$monitor"/*; do
+        [ -d "$nested_dir" ] || continue
+        nested=$(basename "$nested_dir")
+        test_monitor_reactor "$nested" "$monitor/"
+    done
+}
+
+for monitor_dir in monitors/*; do
+    monitor=$(basename "$monitor_dir")
+
+    if find "$monitor_dir" -mindepth 1 -type d | grep -q .; then
+        test_container_monitor "$monitor"
+    else
+        test_monitor_reactor "$monitor"
+    fi
+done
+
+monitor=$(ls /sys/kernel/tracing/rv/monitors -1 | head -n 1)
+test -f "monitors/$monitor/reactors"
+! echo non_existent_reactor > "monitors/$monitor/reactors"
+! grep -q "\\[non_existent_reactor\\]" "monitors/$monitor/reactors"

tools/testing/selftests/verification/test.d/rv_monitors_available.tc

@@ -0,0 +1,18 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-or-later
+# description: Check available monitors
+
+for monitor_dir in monitors/*; do
+    monitor=$(basename "$monitor_dir")
+
+    grep -q "^$monitor$" available_monitors
+    grep -q . "$monitor_dir"/desc
+
+    for nested_dir in "$monitor_dir"/*; do
+        [ -d "$nested_dir" ] || continue
+        nested=$(basename "$nested_dir")
+
+        grep -q "^$monitor:$nested$" available_monitors
+		grep -q . "$nested_dir"/desc
+    done
+done

tools/testing/selftests/verification/test.d/rv_wwnr_printk.tc

@@ -0,0 +1,30 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-or-later
+# description: Test wwnr monitor with printk reactor
+# requires: available_reactors wwnr:monitor printk:reactor stress-ng:program
+
+load() { # returns true if there was a reaction
+	local lines_before num
+	num=$((($(nproc) + 1) / 2))
+	lines_before=$(dmesg | wc -l)
+	stress-ng --cpu-sched "$num" --timer "$num" -t 5 -q
+	dmesg | tail -n $((lines_before + 1)) | grep -q "rv: monitor wwnr does not allow event"
+}
+
+echo 1 > monitors/wwnr/enable
+echo printk > monitors/wwnr/reactors
+
+load
+
+echo 0 > monitoring_on
+! load
+echo 1 > monitoring_on
+
+load
+
+echo 0 > reacting_on
+! load
+echo 1 > reacting_on
+
+echo nop > monitors/wwnr/reactors
+echo 0 > monitors/wwnr/enable

tools/testing/selftests/verification/verificationtest-ktap

@@ -0,0 +1,8 @@
+#!/bin/sh -e
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# ftracetest-ktap: Wrapper to integrate ftracetest with the kselftest runner
+#
+# Copyright (C) Arm Ltd., 2023
+
+../ftrace/ftracetest -K -v --rv ../verification