kINT: Fix synchronization problem

The reported problem with integrity verification on ARM64 (#269)
is a result of a very tight race condition with tracepoints.
Changes which simplify synchronization with JUMP_LABEL engine:
f98da1b
affected differently ARM64 platform which made such race possible.
However, potentially the same race problem may exist on x86 and
this commit fixes it and should address #269

src/modules/database/p_database.c

@@ -191,6 +191,7 @@ int p_create_database(void) {
 
  P_SYM_INIT(jump_label_mutex)
  P_SYM_INIT(text_mutex)
+ P_SYM_INIT(tracepoints_mutex)
 
  /*
  * First gather information about CPUs in the system - CRITICAL !!!

src/modules/database/p_database.h

@@ -205,6 +205,7 @@ static inline void p_text_section_lock(void) {
  mutex_lock(P_SYM(p_module_mutex));
  while (mutex_is_locked(P_SYM(p_jump_label_mutex)))
  schedule();
+ mutex_lock(P_SYM(p_tracepoints_mutex));
 #if defined(P_LKRG_CI_ARCH_STATIC_CALL_TRANSFORM_H)
  do {
  p_lkrg_counter_lock_lock(&p_static_call_spinlock, &p_text_flags);
@@ -225,6 +226,7 @@ static inline void p_text_section_unlock(void) {
 #if defined(P_LKRG_CI_ARCH_STATIC_CALL_TRANSFORM_H)
  p_lkrg_counter_lock_val_dec(&p_static_call_spinlock);
 #endif
+ mutex_unlock(P_SYM(p_tracepoints_mutex));
  /* Release the 'module_mutex' */
  mutex_unlock(P_SYM(p_module_mutex));
 #if defined(CONFIG_DYNAMIC_FTRACE)

src/p_lkrg_main.h

@@ -237,6 +237,7 @@ typedef struct _p_lkrg_global_symbols_structure {
  pmd_t *(*p_mm_find_pmd)(struct mm_struct *mm, unsigned long address);
  struct mutex *p_jump_label_mutex;
  struct mutex *p_text_mutex;
+ struct mutex *p_tracepoints_mutex;
  struct text_poke_loc **p_tp_vec;
  int *p_tp_vec_nr;
 #if defined(CONFIG_DYNAMIC_DEBUG)