Merge tag 'trace-v6.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix filter memory leak by calling ftrace_free_filter()

 - Initialize trace_printk() earlier so that ftrace_dump_on_oops shows
   data on early crashes.

 - Update the outdated instructions in scripts/tracing/ftrace-bisect.sh

 - Add lockdep_is_held() to fix lockdep warning

 - Add allocation failure check in create_hist_field()

 - Don't initialize pointer that gets set right away in enabled_monitors_write()

 - Update MAINTAINER entries

 - Fix help messages in Kconfigs

 - Fix kernel-doc header for update_preds()

* tag 'trace-v6.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  bootconfig: Update MAINTAINERS file to add tree and mailing list
  rv: remove redundant initialization of pointer ptr
  ftrace: Maintain samples/ftrace
  tracing/filter: fix kernel-doc warnings
  lib: Kconfig: fix spellos
  trace_events_hist: add check for return value of 'create_hist_field'
  tracing/osnoise: Use built-in RCU list checking
  tracing: Kconfig: Fix spelling/grammar/punctuation
  ftrace/scripts: Update the instructions for ftrace-bisect.sh
  tracing: Make sure trace_printk() can output as soon as it can be used
  ftrace: Export ftrace_free_filter() to modules

1 files changed, 22 insertions, 1 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 442438b93fe9..750aa3f08b25 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1248,12 +1248,17 @@ static void free_ftrace_hash_rcu(struct ftrace_hash *hash)
 	call_rcu(&hash->rcu, __free_ftrace_hash_rcu);
 }
 
+/**
+ * ftrace_free_filter - remove all filters for an ftrace_ops
+ * @ops - the ops to remove the filters from
+ */
 void ftrace_free_filter(struct ftrace_ops *ops)
 {
 	ftrace_ops_init(ops);
 	free_ftrace_hash(ops->func_hash->filter_hash);
 	free_ftrace_hash(ops->func_hash->notrace_hash);
 }
+EXPORT_SYMBOL_GPL(ftrace_free_filter);
 
 static struct ftrace_hash *alloc_ftrace_hash(int size_bits)
 {
@@ -5839,6 +5844,10 @@ EXPORT_SYMBOL_GPL(modify_ftrace_direct_multi);
  *
  * Filters denote which functions should be enabled when tracing is enabled
  * If @ip is NULL, it fails to update filter.
+ *
+ * This can allocate memory which must be freed before @ops can be freed,
+ * either by removing each filtered addr or by using
+ * ftrace_free_filter(@ops).
  */
 int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
 			 int remove, int reset)
@@ -5858,7 +5867,11 @@ EXPORT_SYMBOL_GPL(ftrace_set_filter_ip);
  *
  * Filters denote which functions should be enabled when tracing is enabled
  * If @ips array or any ip specified within is NULL , it fails to update filter.
- */
+ *
+ * This can allocate memory which must be freed before @ops can be freed,
+ * either by removing each filtered addr or by using
+ * ftrace_free_filter(@ops).
+*/
 int ftrace_set_filter_ips(struct ftrace_ops *ops, unsigned long *ips,
 			  unsigned int cnt, int remove, int reset)
 {
@@ -5900,6 +5913,10 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
  *
  * Filters denote which functions should be enabled when tracing is enabled.
  * If @buf is NULL and reset is set, all functions will be enabled for tracing.
+ *
+ * This can allocate memory which must be freed before @ops can be freed,
+ * either by removing each filtered addr or by using
+ * ftrace_free_filter(@ops).
  */
 int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
 		       int len, int reset)
@@ -5919,6 +5936,10 @@ EXPORT_SYMBOL_GPL(ftrace_set_filter);
  * Notrace Filters denote which functions should not be enabled when tracing
  * is enabled. If @buf is NULL and reset is set, all functions will be enabled
  * for tracing.
+ *
+ * This can allocate memory which must be freed before @ops can be freed,
+ * either by removing each filtered addr or by using
+ * ftrace_free_filter(@ops).
  */
 int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
 			int len, int reset)