tree:   git://git.cmpxchg.org/linux-mmotm.git master
head:   60319c74c8a7816a4b392f51a12a77cde302262b
commit: 7a5f64d9a72a65046cfdc05a02f84e6462ae5bff [332/380] mm: rcu-protected get_mm_exe_file()
config: microblaze-allyesconfig (attached as .config)
reproduce:
  wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
  chmod +x ~/bin/make.cross
  git checkout 7a5f64d9a72a65046cfdc05a02f84e6462ae5bff
  # save the attached .config to linux build tree
  make.cross ARCH=microblaze 

All warnings:

   In file included from include/linux/srcu.h:33:0,
                    from include/linux/notifier.h:15,
                    from include/linux/memory_hotplug.h:6,
                    from include/linux/mmzone.h:790,
                    from include/linux/gfp.h:5,
                    from include/linux/slab.h:14,
                    from kernel/fork.c:14:
   kernel/fork.c: In function 'set_mm_exe_file':
   kernel/fork.c:699:4: warning: passing argument 1 of 'lock_is_held' from incompatible pointer type
       lock_is_held(&mm->mmap_sem));
       ^
   include/linux/rcupdate.h:528:53: note: in definition of macro 'rcu_lockdep_assert'
      if (debug_lockdep_rcu_enabled() && !__warned && !(c)) { \
                                                        ^
>> include/linux/rcupdate.h:810:2: note: in expansion of macro '__rcu_dereference_protected'
     __rcu_dereference_protected((p), (c), __rcu)
     ^
>> kernel/fork.c:697:30: note: in expansion of macro 'rcu_dereference_protected'
     struct file *old_exe_file = rcu_dereference_protected(mm->exe_file,
                                 ^
   In file included from include/linux/spinlock_types.h:18:0,
                    from include/linux/spinlock.h:81,
                    from include/linux/mmzone.h:7,
                    from include/linux/gfp.h:5,
                    from include/linux/slab.h:14,
                    from kernel/fork.c:14:
   include/linux/lockdep.h:341:12: note: expected 'struct lockdep_map *' but argument is of type 'struct rw_semaphore *'
    extern int lock_is_held(struct lockdep_map *lock);
               ^

vim +/rcu_dereference_protected +697 kernel/fork.c

   691	 * Main users are mmput(), sys_execve() and sys_prctl(PR_SET_MM_MAP/EXE_FILE).
   692	 * Callers prevent concurrent invocations: in mmput() nobody alive left,
   693	 * in execve task is single-threaded, prctl holds mmap_sem exclusively.
   694	 */
   695	void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file)
   696	{
 > 697		struct file *old_exe_file = rcu_dereference_protected(mm->exe_file,
   698				!atomic_read(&mm->mm_users) || current->in_execve ||
 > 699				lock_is_held(&mm->mmap_sem));
   700	
   701		if (new_exe_file)
   702			get_file(new_exe_file);

---
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