Merge tag 'trace-rv-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull runtime verification updates from Steven Rostedt:

 - Added Linear temporal logic monitors for RT application

   Real-time applications may have design flaws causing them to have
   unexpected latency. For example, the applications may raise page
   faults, or may be blocked trying to take a mutex without priority
   inheritance.

   However, while attempting to implement DA monitors for these
   real-time rules, deterministic automaton is found to be inappropriate
   as the specification language. The automaton is complicated, hard to
   understand, and error-prone.

   For these cases, linear temporal logic is found to be more suitable.
   The LTL is more concise and intuitive.

 - Make printk_deferred() public

   The new monitors needed access to printk_deferred(). Make them
   visible for the entire kernel.

 - Add a vpanic() to allow for va_list to be passed to panic.

 - Add rtapp container monitor.

   A collection of monitors that check for common problems with
   real-time applications that cause unexpected latency.

 - Add page fault tracepoints to risc-v

   These tracepoints are necessary to for the RV monitor to run on
   risc-v.

 - Fix the behaviour of the rv tool with -s and idle tasks.

 - Allow the rv tool to gracefully terminate with SIGTERM

 - Adjusts dot2c not to create lines over 100 columns

 - Properly order nested monitors in the RV Kconfig file

 - Return the registration error in all DA monitor instead of 0

 - Update and add new sched collection monitors

   Replace tss and sncid monitors with more complete sts:

   Not only prove that switches occur in scheduling context and scheduling
   needs interrupt disabled but also that each call to the scheduler
   disables interrupts to (optionally) switch.

   New monitor: nrp
     Preemption requires need resched which is cleared by any switch
     (includes a non optimal workaround for /nested/ preemptions)

   New monitor: sssw
     suspension requires setting the task to sleepable and, after the
     switch occurs, the task requires a wakeup to come back to runnable

   New monitor: opid
      waking and need-resched operations occur with interrupts and
      preemption disabled or in IRQ without explicitly disabling
      preemption"

* tag 'trace-rv-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (48 commits)
  rv: Add opid per-cpu monitor
  rv: Add nrp and sssw per-task monitors
  rv: Replace tss and sncid monitors with more complete sts
  sched: Adapt sched tracepoints for RV task model
  rv: Retry when da monitor detects race conditions
  rv: Adjust monitor dependencies
  rv: Use strings in da monitors tracepoints
  rv: Remove trailing whitespace from tracepoint string
  rv: Add da_handle_start_run_event_ to per-task monitors
  rv: Fix wrong type cast in reactors_show() and monitor_reactor_show()
  rv: Fix wrong type cast in monitors_show()
  rv: Remove struct rv_monitor::reacting
  rv: Remove rv_reactor's reference counter
  rv: Merge struct rv_reactor_def into struct rv_reactor
  rv: Merge struct rv_monitor_def into struct rv_monitor
  rv: Remove unused field in struct rv_monitor_def
  rv: Return init error when registering monitors
  verification/rvgen: Organise Kconfig entries for nested monitors
  tools/dot2c: Fix generated files going over 100 column limit
  tools/rv: Stop gracefully also on SIGTERM
  ...

1 files changed, 13 insertions, 5 deletions

diff --git a/kernel/panic.c b/kernel/panic.c
index 64e58835086d..43817111c979 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -367,15 +367,15 @@ static void panic_other_cpus_shutdown(bool crash_kexec)
 }
 
 /**
- * panic - halt the system
+ * vpanic - halt the system
  * @fmt: The text string to print
+ * @args: Arguments for the format string
  *
  * Display a message, then perform cleanups. This function never returns.
  */
-void panic(const char *fmt, ...)
+void vpanic(const char *fmt, va_list args)
 {
 	static char buf[1024];
-	va_list args;
 	long i, i_next = 0, len;
 	int state = 0;
 	int old_cpu, this_cpu;
@@ -426,9 +426,7 @@ void panic(const char *fmt, ...)
 
 	console_verbose();
 	bust_spinlocks(1);
-	va_start(args, fmt);
 	len = vscnprintf(buf, sizeof(buf), fmt, args);
-	va_end(args);
 
 	if (len && buf[len - 1] == '\n')
 		buf[len - 1] = '\0';
@@ -565,7 +563,17 @@ void panic(const char *fmt, ...)
 		mdelay(PANIC_TIMER_STEP);
 	}
 }
+EXPORT_SYMBOL(vpanic);
 
+/* Identical to vpanic(), except it takes variadic arguments instead of va_list */
+void panic(const char *fmt, ...)
+{
+	va_list args;
+
+	va_start(args, fmt);
+	vpanic(fmt, args);
+	va_end(args);
+}
 EXPORT_SYMBOL(panic);
 
 #define TAINT_FLAG(taint, _c_true, _c_false, _module)			\