Merge tag 'trace-v6.19-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-traceHEADmaster

Pull tracing fixes from Steven Rostedt:

 - Remove useless assignment of soft_mode variable

   The function __ftrace_event_enable_disable() sets "soft_mode" in one
   of the branch paths but doesn't use it after that. Remove the setting
   of that variable.

 - Add a cond_resched() in ring_buffer_resize()

   The resize function that allocates all the pages for the ring buffer
   was causing a soft lockup on PREEMPT_NONE configs when allocating
   large buffers on machines with many CPUs. Hopefully this is the last
   cond_resched() needed to be added as PREEMPT_LAZY becomes the norm in
   the future.

 - Make ftrace_graph_ent depth field signed

   The "depth" field of struct ftrace_graph_ent was converted from "int"
   to "unsigned long" for alignment reasons to work with being embedded
   in other structures. The conversion from a signed to unsigned caused
   integrity checks to always pass as they were comparing "depth" to
   less than zero. Make the field signed long.

 - Add recursion protection to stack trace events

   A infinite recursion was triggered by a stack trace event calling RCU
   which internally called rcu_read_unlock_special(), which triggered an
   event that was also doing stacktraces which cause it to trigger the
   same RCU lock that called rcu_read_unlock_special() again.

   Update the trace_test_and_set_recursion() to add a set of context
   checks for events to use, and have the stack trace event use that for
   recursion protection.

 - Make the variable ftrace_dump_on_oops static

   The cleanup of sysctl that moved all the updates to the files that
   use them moved the reference of ftrace_dump_on_oops to where it is
   used. It is no longer used outside of the trace.c file. Make it
   static.

* tag 'trace-v6.19-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  trace: ftrace_dump_on_oops[] is not exported, make it static
  tracing: Add recursion protection in kernel stack trace recording
  ftrace: Make ftrace_graph_ent depth field signed
  ring-buffer: Avoid softlockup in ring_buffer_resize() during memory free
  tracing: Drop unneeded assignment to soft_mode

2 files changed, 10 insertions, 1 deletions

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 770f0dc993cc..a3a8989e3268 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -1167,7 +1167,7 @@ static inline void ftrace_init(void) { }
  */
 struct ftrace_graph_ent {
 	unsigned long func; /* Current function */
-	unsigned long depth;
+	long depth; /* signed to check for less than zero */
 } __packed;
 
 /*
diff --git a/include/linux/trace_recursion.h b/include/linux/trace_recursion.h
index ae04054a1be3..e6ca052b2a85 100644
--- a/include/linux/trace_recursion.h
+++ b/include/linux/trace_recursion.h
@@ -34,6 +34,13 @@ enum {
 	TRACE_INTERNAL_SIRQ_BIT,
 	TRACE_INTERNAL_TRANSITION_BIT,
 
+	/* Internal event use recursion bits */
+	TRACE_INTERNAL_EVENT_BIT,
+	TRACE_INTERNAL_EVENT_NMI_BIT,
+	TRACE_INTERNAL_EVENT_IRQ_BIT,
+	TRACE_INTERNAL_EVENT_SIRQ_BIT,
+	TRACE_INTERNAL_EVENT_TRANSITION_BIT,
+
 	TRACE_BRANCH_BIT,
 /*
  * Abuse of the trace_recursion.
@@ -58,6 +65,8 @@ enum {
 
 #define TRACE_LIST_START	TRACE_INTERNAL_BIT
 
+#define TRACE_EVENT_START	TRACE_INTERNAL_EVENT_BIT
+
 #define TRACE_CONTEXT_MASK	((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
 
 /*