ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

15 files changed, 303 insertions, 0 deletions

diff --git a/tools/verification/models/deadline/nomiss.dot b/tools/verification/models/deadline/nomiss.dot
new file mode 100644
index 000000000..fd1ea6bf2
--- /dev/null
+++ b/tools/verification/models/deadline/nomiss.dot
@@ -0,0 +1,41 @@
+digraph state_automaton {
+	center = true;
+	size = "7,11";
+	{node [shape = circle] "idle"};
+	{node [shape = plaintext, style=invis, label=""] "__init_ready"};
+	{node [shape = doublecircle] "ready"};
+	{node [shape = circle] "ready"};
+	{node [shape = circle] "running"};
+	{node [shape = circle] "sleeping"};
+	{node [shape = circle] "throttled"};
+	"__init_ready" -> "ready";
+	"idle" [label = "idle"];
+	"idle" -> "idle" [ label = "dl_server_idle" ];
+	"idle" -> "ready" [ label = "dl_replenish;reset(clk)" ];
+	"idle" -> "running" [ label = "sched_switch_in" ];
+	"idle" -> "sleeping" [ label = "dl_server_stop" ];
+	"idle" -> "throttled" [ label = "dl_throttle" ];
+	"ready" [label = "ready\nclk < DEADLINE_NS()", color = green3];
+	"ready" -> "idle" [ label = "dl_server_idle" ];
+	"ready" -> "ready" [ label = "sched_wakeup\ndl_replenish;reset(clk)" ];
+	"ready" -> "running" [ label = "sched_switch_in" ];
+	"ready" -> "sleeping" [ label = "dl_server_stop" ];
+	"ready" -> "throttled" [ label = "dl_throttle;is_defer == 1" ];
+	"running" [label = "running\nclk < DEADLINE_NS()"];
+	"running" -> "idle" [ label = "dl_server_idle" ];
+	"running" -> "running" [ label = "dl_replenish;reset(clk)\nsched_switch_in\nsched_wakeup" ];
+	"running" -> "sleeping" [ label = "sched_switch_suspend\ndl_server_stop" ];
+	"running" -> "throttled" [ label = "dl_throttle" ];
+	"sleeping" [label = "sleeping"];
+	"sleeping" -> "ready" [ label = "sched_wakeup\ndl_replenish;reset(clk)" ];
+	"sleeping" -> "running" [ label = "sched_switch_in" ];
+	"sleeping" -> "sleeping" [ label = "dl_server_stop\ndl_server_idle" ];
+	"sleeping" -> "throttled" [ label = "dl_throttle;is_constr_dl == 1 || is_defer == 1" ];
+	"throttled" [label = "throttled"];
+	"throttled" -> "ready" [ label = "dl_replenish;reset(clk)" ];
+	"throttled" -> "throttled" [ label = "sched_switch_suspend\nsched_wakeup\ndl_server_idle\ndl_throttle" ];
+	{ rank = min ;
+		"__init_ready";
+		"ready";
+	}
+}
diff --git a/tools/verification/models/rtapp/pagefault.ltl b/tools/verification/models/rtapp/pagefault.ltl
new file mode 100644
index 000000000..d7ce62102
--- /dev/null
+++ b/tools/verification/models/rtapp/pagefault.ltl
@@ -0,0 +1 @@
+RULE = always (RT imply not PAGEFAULT)
diff --git a/tools/verification/models/rtapp/sleep.ltl b/tools/verification/models/rtapp/sleep.ltl
new file mode 100644
index 000000000..4d78fdd20
--- /dev/null
+++ b/tools/verification/models/rtapp/sleep.ltl
@@ -0,0 +1,20 @@
+RULE = always ((RT and SLEEP and USER_THREAD) imply (RT_FRIENDLY_SLEEP or ALLOWLIST))
+
+RT_FRIENDLY_SLEEP = RT_VALID_SLEEP_REASON
+                and ((not SCHEDULE_IN) until RT_FRIENDLY_WAKE)
+
+RT_VALID_SLEEP_REASON = FUTEX_WAIT
+                     or RT_FRIENDLY_NANOSLEEP
+                     or EPOLL_WAIT
+
+RT_FRIENDLY_NANOSLEEP = CLOCK_NANOSLEEP
+                    and NANOSLEEP_TIMER_ABSTIME
+                    and not NANOSLEEP_CLOCK_REALTIME
+
+RT_FRIENDLY_WAKE = WOKEN_BY_EQUAL_OR_HIGHER_PRIO
+                or WOKEN_BY_HARDIRQ
+                or WOKEN_BY_NMI
+                or ABORT_SLEEP
+
+ALLOWLIST = BLOCK_ON_RT_MUTEX
+         or FUTEX_LOCK_PI
diff --git a/tools/verification/models/rtapp/wakeup.ltl b/tools/verification/models/rtapp/wakeup.ltl
new file mode 100644
index 000000000..a5d63ca08
--- /dev/null
+++ b/tools/verification/models/rtapp/wakeup.ltl
@@ -0,0 +1,5 @@
+RULE = always (((RT and USER_THREAD) imply
+		(not (WOKEN_BY_LOWER_PRIO or WOKEN_BY_SOFTIRQ)) or ALLOWLIST))
+
+ALLOWLIST = BLOCK_ON_RT_MUTEX
+         or FUTEX_LOCK_PI
diff --git a/tools/verification/models/sched/nrp.dot b/tools/verification/models/sched/nrp.dot
new file mode 100644
index 000000000..77bb64669
--- /dev/null
+++ b/tools/verification/models/sched/nrp.dot
@@ -0,0 +1,29 @@
+digraph state_automaton {
+	center = true;
+	size = "7,11";
+	{node [shape = doublecircle] "any_thread_running"};
+	{node [shape = circle] "any_thread_running"};
+	{node [shape = circle] "nested_preempt"};
+	{node [shape = plaintext, style=invis, label=""] "__init_preempt_irq"};
+	{node [shape = circle] "preempt_irq"};
+	{node [shape = circle] "rescheduling"};
+	"__init_preempt_irq" -> "preempt_irq";
+	"any_thread_running" [label = "any_thread_running", color = green3];
+	"any_thread_running" -> "any_thread_running" [ label = "schedule_entry\nirq_entry" ];
+	"any_thread_running" -> "rescheduling" [ label = "sched_need_resched" ];
+	"nested_preempt" [label = "nested_preempt"];
+	"nested_preempt" -> "any_thread_running" [ label = "schedule_entry_preempt\nschedule_entry" ];
+	"nested_preempt" -> "nested_preempt" [ label = "irq_entry" ];
+	"nested_preempt" -> "preempt_irq" [ label = "sched_need_resched" ];
+	"preempt_irq" [label = "preempt_irq"];
+	"preempt_irq" -> "nested_preempt" [ label = "schedule_entry_preempt\nschedule_entry" ];
+	"preempt_irq" -> "preempt_irq" [ label = "irq_entry\nsched_need_resched" ];
+	"rescheduling" [label = "rescheduling"];
+	"rescheduling" -> "any_thread_running" [ label = "schedule_entry_preempt\nschedule_entry" ];
+	"rescheduling" -> "preempt_irq" [ label = "irq_entry" ];
+	"rescheduling" -> "rescheduling" [ label = "sched_need_resched" ];
+	{ rank = min ;
+		"__init_preempt_irq";
+		"preempt_irq";
+	}
+}
diff --git a/tools/verification/models/sched/opid.dot b/tools/verification/models/sched/opid.dot
new file mode 100644
index 000000000..511051fce
--- /dev/null
+++ b/tools/verification/models/sched/opid.dot
@@ -0,0 +1,13 @@
+digraph state_automaton {
+	center = true;
+	size = "7,11";
+	{node [shape = plaintext, style=invis, label=""] "__init_any"};
+	{node [shape = doublecircle] "any"};
+	"__init_any" -> "any";
+	"any" [label = "any", color = green3];
+	"any" -> "any" [ label = "sched_need_resched;irq_off == 1\nsched_waking;irq_off == 1 && preempt_off == 1" ];
+	{ rank = min ;
+		"__init_any";
+		"any";
+	}
+}
diff --git a/tools/verification/models/sched/sco.dot b/tools/verification/models/sched/sco.dot
new file mode 100644
index 000000000..20b0e3b44
--- /dev/null
+++ b/tools/verification/models/sched/sco.dot
@@ -0,0 +1,18 @@
+digraph state_automaton {
+	center = true;
+	size = "7,11";
+	{node [shape = plaintext] "scheduling_context"};
+	{node [shape = plaintext, style=invis, label=""] "__init_thread_context"};
+	{node [shape = ellipse] "thread_context"};
+	{node [shape = plaintext] "thread_context"};
+	"__init_thread_context" -> "thread_context";
+	"scheduling_context" [label = "scheduling_context"];
+	"scheduling_context" -> "thread_context" [ label = "schedule_exit" ];
+	"thread_context" [label = "thread_context", color = green3];
+	"thread_context" -> "scheduling_context" [ label = "schedule_entry" ];
+	"thread_context" -> "thread_context" [ label = "sched_set_state" ];
+	{ rank = min ;
+		"__init_thread_context";
+		"thread_context";
+	}
+}
diff --git a/tools/verification/models/sched/scpd.dot b/tools/verification/models/sched/scpd.dot
new file mode 100644
index 000000000..340413896
--- /dev/null
+++ b/tools/verification/models/sched/scpd.dot
@@ -0,0 +1,18 @@
+digraph state_automaton {
+	center = true;
+	size = "7,11";
+	{node [shape = plaintext] "can_sched"};
+	{node [shape = plaintext, style=invis, label=""] "__init_cant_sched"};
+	{node [shape = ellipse] "cant_sched"};
+	{node [shape = plaintext] "cant_sched"};
+	"__init_cant_sched" -> "cant_sched";
+	"can_sched" [label = "can_sched"];
+	"can_sched" -> "can_sched" [ label = "schedule_entry\nschedule_exit" ];
+	"can_sched" -> "cant_sched" [ label = "preempt_enable" ];
+	"cant_sched" [label = "cant_sched", color = green3];
+	"cant_sched" -> "can_sched" [ label = "preempt_disable" ];
+	{ rank = min ;
+		"__init_cant_sched";
+		"cant_sched";
+	}
+}
diff --git a/tools/verification/models/sched/snep.dot b/tools/verification/models/sched/snep.dot
new file mode 100644
index 000000000..fe1300e93
--- /dev/null
+++ b/tools/verification/models/sched/snep.dot
@@ -0,0 +1,18 @@
+digraph state_automaton {
+	center = true;
+	size = "7,11";
+	{node [shape = plaintext, style=invis, label=""] "__init_non_scheduling_context"};
+	{node [shape = ellipse] "non_scheduling_context"};
+	{node [shape = plaintext] "non_scheduling_context"};
+	{node [shape = plaintext] "scheduling_contex"};
+	"__init_non_scheduling_context" -> "non_scheduling_context";
+	"non_scheduling_context" [label = "non_scheduling_context", color = green3];
+	"non_scheduling_context" -> "non_scheduling_context" [ label = "preempt_disable\npreempt_enable" ];
+	"non_scheduling_context" -> "scheduling_contex" [ label = "schedule_entry" ];
+	"scheduling_contex" [label = "scheduling_contex"];
+	"scheduling_contex" -> "non_scheduling_context" [ label = "schedule_exit" ];
+	{ rank = min ;
+		"__init_non_scheduling_context";
+		"non_scheduling_context";
+	}
+}
diff --git a/tools/verification/models/sched/snroc.dot b/tools/verification/models/sched/snroc.dot
new file mode 100644
index 000000000..8b71c32d4
--- /dev/null
+++ b/tools/verification/models/sched/snroc.dot
@@ -0,0 +1,18 @@
+digraph state_automaton {
+	center = true;
+	size = "7,11";
+	{node [shape = plaintext, style=invis, label=""] "__init_other_context"};
+	{node [shape = ellipse] "other_context"};
+	{node [shape = plaintext] "other_context"};
+	{node [shape = plaintext] "own_context"};
+	"__init_other_context" -> "other_context";
+	"other_context" [label = "other_context", color = green3];
+	"other_context" -> "own_context" [ label = "sched_switch_in" ];
+	"own_context" [label = "own_context"];
+	"own_context" -> "other_context" [ label = "sched_switch_out" ];
+	"own_context" -> "own_context" [ label = "sched_set_state" ];
+	{ rank = min ;
+		"__init_other_context";
+		"other_context";
+	}
+}
diff --git a/tools/verification/models/sched/sssw.dot b/tools/verification/models/sched/sssw.dot
new file mode 100644
index 000000000..4994c3e87
--- /dev/null
+++ b/tools/verification/models/sched/sssw.dot
@@ -0,0 +1,30 @@
+digraph state_automaton {
+	center = true;
+	size = "7,11";
+	{node [shape = plaintext, style=invis, label=""] "__init_runnable"};
+	{node [shape = doublecircle] "runnable"};
+	{node [shape = circle] "runnable"};
+	{node [shape = circle] "signal_wakeup"};
+	{node [shape = circle] "sleepable"};
+	{node [shape = circle] "sleeping"};
+	"__init_runnable" -> "runnable";
+	"runnable" [label = "runnable", color = green3];
+	"runnable" -> "runnable" [ label = "sched_set_state_runnable\nsched_wakeup\nsched_switch_in\nsched_switch_yield\nsched_switch_preempt\nsignal_deliver" ];
+	"runnable" -> "sleepable" [ label = "sched_set_state_sleepable" ];
+	"runnable" -> "sleeping" [ label = "sched_switch_blocking" ];
+	"signal_wakeup" [label = "signal_wakeup"];
+	"signal_wakeup" -> "runnable" [ label = "signal_deliver" ];
+	"signal_wakeup" -> "signal_wakeup" [ label = "sched_switch_in\nsched_switch_preempt\nsched_switch_yield\nsched_wakeup" ];
+	"signal_wakeup" -> "sleepable" [ label = "sched_set_state_sleepable" ];
+	"sleepable" [label = "sleepable"];
+	"sleepable" -> "runnable" [ label = "sched_set_state_runnable\nsched_wakeup" ];
+	"sleepable" -> "signal_wakeup" [ label = "sched_switch_yield" ];
+	"sleepable" -> "sleepable" [ label = "sched_set_state_sleepable\nsched_switch_in\nsched_switch_preempt\nsignal_deliver" ];
+	"sleepable" -> "sleeping" [ label = "sched_switch_suspend\nsched_switch_blocking" ];
+	"sleeping" [label = "sleeping"];
+	"sleeping" -> "runnable" [ label = "sched_wakeup" ];
+	{ rank = min ;
+		"__init_runnable";
+		"runnable";
+	}
+}
diff --git a/tools/verification/models/sched/sts.dot b/tools/verification/models/sched/sts.dot
new file mode 100644
index 000000000..8f5f38be0
--- /dev/null
+++ b/tools/verification/models/sched/sts.dot
@@ -0,0 +1,38 @@
+digraph state_automaton {
+	center = true;
+	size = "7,11";
+	{node [shape = plaintext, style=invis, label=""] "__init_can_sched"};
+	{node [shape = doublecircle] "can_sched"};
+	{node [shape = circle] "can_sched"};
+	{node [shape = circle] "cant_sched"};
+	{node [shape = circle] "disable_to_switch"};
+	{node [shape = circle] "enable_to_exit"};
+	{node [shape = circle] "in_irq"};
+	{node [shape = circle] "scheduling"};
+	{node [shape = circle] "switching"};
+	"__init_can_sched" -> "can_sched";
+	"can_sched" [label = "can_sched", color = green3];
+	"can_sched" -> "cant_sched" [ label = "irq_disable" ];
+	"can_sched" -> "scheduling" [ label = "schedule_entry" ];
+	"cant_sched" [label = "cant_sched"];
+	"cant_sched" -> "can_sched" [ label = "irq_enable" ];
+	"cant_sched" -> "cant_sched" [ label = "irq_entry" ];
+	"disable_to_switch" [label = "disable_to_switch"];
+	"disable_to_switch" -> "enable_to_exit" [ label = "irq_enable" ];
+	"disable_to_switch" -> "in_irq" [ label = "irq_entry" ];
+	"disable_to_switch" -> "switching" [ label = "sched_switch" ];
+	"enable_to_exit" [label = "enable_to_exit"];
+	"enable_to_exit" -> "can_sched" [ label = "schedule_exit" ];
+	"enable_to_exit" -> "enable_to_exit" [ label = "irq_disable\nirq_entry\nirq_enable" ];
+	"in_irq" [label = "in_irq"];
+	"in_irq" -> "in_irq" [ label = "irq_entry" ];
+	"in_irq" -> "scheduling" [ label = "irq_enable" ];
+	"scheduling" [label = "scheduling"];
+	"scheduling" -> "disable_to_switch" [ label = "irq_disable" ];
+	"switching" [label = "switching"];
+	"switching" -> "enable_to_exit" [ label = "irq_enable" ];
+	{ rank = min ;
+		"__init_can_sched";
+		"can_sched";
+	}
+}
diff --git a/tools/verification/models/stall.dot b/tools/verification/models/stall.dot
new file mode 100644
index 000000000..50077d1df
--- /dev/null
+++ b/tools/verification/models/stall.dot
@@ -0,0 +1,22 @@
+digraph state_automaton {
+	center = true;
+	size = "7,11";
+	{node [shape = circle] "enqueued"};
+	{node [shape = plaintext, style=invis, label=""] "__init_dequeued"};
+	{node [shape = doublecircle] "dequeued"};
+	{node [shape = circle] "running"};
+	"__init_dequeued" -> "dequeued";
+	"enqueued" [label = "enqueued\nclk < threshold_jiffies"];
+	"running" [label = "running"];
+	"dequeued" [label = "dequeued", color = green3];
+	"running" -> "running" [ label = "sched_switch_in\nsched_wakeup" ];
+	"enqueued" -> "enqueued" [ label = "sched_wakeup" ];
+	"enqueued" -> "running" [ label = "sched_switch_in" ];
+	"running" -> "dequeued" [ label = "sched_switch_wait" ];
+	"dequeued" -> "enqueued" [ label = "sched_wakeup;reset(clk)" ];
+	"running" -> "enqueued" [ label = "sched_switch_preempt;reset(clk)" ];
+	{ rank = min ;
+		"__init_dequeued";
+		"dequeued";
+	}
+}
diff --git a/tools/verification/models/wip.dot b/tools/verification/models/wip.dot
new file mode 100644
index 000000000..2a53a9700
--- /dev/null
+++ b/tools/verification/models/wip.dot
@@ -0,0 +1,16 @@
+digraph state_automaton {
+	{node [shape = circle] "non_preemptive"};
+	{node [shape = plaintext, style=invis, label=""] "__init_preemptive"};
+	{node [shape = doublecircle] "preemptive"};
+	{node [shape = circle] "preemptive"};
+	"__init_preemptive" -> "preemptive";
+	"non_preemptive" [label = "non_preemptive"];
+	"non_preemptive" -> "non_preemptive" [ label = "sched_waking" ];
+	"non_preemptive" -> "preemptive" [ label = "preempt_enable" ];
+	"preemptive" [label = "preemptive"];
+	"preemptive" -> "non_preemptive" [ label = "preempt_disable" ];
+	{ rank = min ;
+		"__init_preemptive";
+		"preemptive";
+	}
+}
diff --git a/tools/verification/models/wwnr.dot b/tools/verification/models/wwnr.dot
new file mode 100644
index 000000000..1b206e831
--- /dev/null
+++ b/tools/verification/models/wwnr.dot
@@ -0,0 +1,16 @@
+digraph state_automaton {
+	{node [shape = plaintext, style=invis, label=""] "__init_not_running"};
+	{node [shape = ellipse] "not_running"};
+	{node [shape = plaintext] "not_running"};
+	{node [shape = plaintext] "running"};
+	"__init_not_running" -> "not_running";
+	"not_running" [label = "not_running", color = green3];
+	"not_running" -> "not_running" [ label = "wakeup" ];
+	"not_running" -> "running" [ label = "switch_in" ];
+	"running" [label = "running"];
+	"running" -> "not_running" [ label = "switch_out" ];
+	{ rank = min ;
+		"__init_not_running";
+		"not_running";
+	}
+}