[selinuxproject-selinux:stable-5.15 1/1] include/linux/rcupdate.h:395:2: warning: passing argument 1 of 'security_locked_down' discards 'const' qualifier from pointer target type

[kernel test robot]

tree:   https://github.com/SELinuxProject/selinux-kernel stable-5.15
head:   c491f0a471580712a4254adece400c3ebb3d8e44
commit: c491f0a471580712a4254adece400c3ebb3d8e44 [1/1] lockdown,selinux: fix wrong subject in some SELinux lockdown checks
config: um-x86_64_defconfig (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://github.com/SELinuxProject/selinux-kernel/commit/c491f0a471580712a4254adece400c3ebb3d8e44
        git remote add selinuxproject-selinux https://github.com/SELinuxProject/selinux-kernel
        git fetch --no-tags selinuxproject-selinux stable-5.15
        git checkout c491f0a471580712a4254adece400c3ebb3d8e44
        # save the attached .config to linux build tree
        make W=1 ARCH=um SUBARCH=x86_64

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

   In file included from include/linux/rbtree.h:24,
                    from include/linux/mm_types.h:10,
                    from include/linux/mmzone.h:21,
                    from include/linux/gfp.h:6,
                    from include/linux/mm.h:10,
                    from drivers/char/mem.c:12:
   drivers/char/mem.c: In function 'open_port':
>> include/linux/rcupdate.h:395:2: warning: passing argument 1 of 'security_locked_down' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
     395 | ({ \
         | ~^~~
     396 |  RCU_LOCKDEP_WARN(!(c), "suspicious rcu_dereference_protected() usage"); \
         |  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     397 |  rcu_check_sparse(p, space); \
         |  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     398 |  ((typeof(*p) __force __kernel *)(p)); \
         |  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     399 | })
         | ~~
   include/linux/rcupdate.h:587:2: note: in expansion of macro '__rcu_dereference_protected'
     587 |  __rcu_dereference_protected((p), (c), __rcu)
         |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/cred.h:299:2: note: in expansion of macro 'rcu_dereference_protected'
     299 |  rcu_dereference_protected(current->cred, 1)
         |  ^~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/char/mem.c:620:28: note: in expansion of macro 'current_cred'
     620 |  rc = security_locked_down(current_cred(), LOCKDOWN_DEV_MEM);
         |                            ^~~~~~~~~~~~
   In file included from include/linux/fs_context.h:14,
                    from include/linux/fs_parser.h:11,
                    from include/linux/shmem_fs.h:11,
                    from drivers/char/mem.c:25:
   include/linux/security.h:1347:53: note: expected 'struct cred *' but argument is of type 'const struct cred *'
    1347 | static inline int security_locked_down(struct cred *cred, enum lockdown_reason what)
         |                                        ~~~~~~~~~~~~~^~~~


vim +395 include/linux/rcupdate.h

76c8eaafe4f061 Paul E. McKenney        2021-04-21  379  
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  380  #define __rcu_access_pointer(p, space) \
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  381  ({ \
7d0ae8086b8283 Paul E. McKenney        2015-03-03  382  	typeof(*p) *_________p1 = (typeof(*p) *__force)READ_ONCE(p); \
423a86a610cad1 Joel Fernandes (Google  2018-12-12  383) 	rcu_check_sparse(p, space); \
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  384  	((typeof(*p) __force __kernel *)(_________p1)); \
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  385  })
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  386  #define __rcu_dereference_check(p, c, space) \
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  387  ({ \
ac59853c06993a Pranith Kumar           2014-11-13  388  	/* Dependency order vs. p above. */ \
506458efaf153c Will Deacon             2017-10-24  389  	typeof(*p) *________p1 = (typeof(*p) *__force)READ_ONCE(p); \
f78f5b90c4ffa5 Paul E. McKenney        2015-06-18  390  	RCU_LOCKDEP_WARN(!(c), "suspicious rcu_dereference_check() usage"); \
423a86a610cad1 Joel Fernandes (Google  2018-12-12  391) 	rcu_check_sparse(p, space); \
ac59853c06993a Pranith Kumar           2014-11-13  392  	((typeof(*p) __force __kernel *)(________p1)); \
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  393  })
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  394  #define __rcu_dereference_protected(p, c, space) \
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28 @395  ({ \
f78f5b90c4ffa5 Paul E. McKenney        2015-06-18  396  	RCU_LOCKDEP_WARN(!(c), "suspicious rcu_dereference_protected() usage"); \
423a86a610cad1 Joel Fernandes (Google  2018-12-12  397) 	rcu_check_sparse(p, space); \
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  398  	((typeof(*p) __force __kernel *)(p)); \
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  399  })
995f1405610bd8 Paul E. McKenney        2016-07-01  400  #define rcu_dereference_raw(p) \
995f1405610bd8 Paul E. McKenney        2016-07-01  401  ({ \
995f1405610bd8 Paul E. McKenney        2016-07-01  402  	/* Dependency order vs. p above. */ \
506458efaf153c Will Deacon             2017-10-24  403  	typeof(p) ________p1 = READ_ONCE(p); \
995f1405610bd8 Paul E. McKenney        2016-07-01  404  	((typeof(*p) __force __kernel *)(________p1)); \
995f1405610bd8 Paul E. McKenney        2016-07-01  405  })
ca5ecddfa8fcbd Paul E. McKenney        2010-04-28  406  

:::::: The code at line 395 was first introduced by commit
:::::: ca5ecddfa8fcbd948c95530e7e817cee9fb43a3d rcu: define __rcu address space modifier for sparse

:::::: TO: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
:::::: CC: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

Attachment: .config.gz
Description: application/gzip