tree: https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git sched/core-sched head: b417ddaf222294bcc35e9857105ab37d9b0fd715 commit: b417ddaf222294bcc35e9857105ab37d9b0fd715 [29/29] sched: prctl() and cgroup interaction config: openrisc-randconfig-r033-20210414 (attached as .config) compiler: or1k-linux-gcc (GCC) 9.3.0 reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/commit/?... git remote add peterz-queue https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git git fetch --no-tags peterz-queue sched/core-sched git checkout b417ddaf222294bcc35e9857105ab37d9b0fd715 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross W=1 ARCH=openrisc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): kernel/sched/core.c:3166:6: warning: no previous prototype for 'sched_set_stop_task' [-Wmissing-prototypes] 3166 | void sched_set_stop_task(int cpu, struct task_struct *stop) | ^~~~~~~~~~~~~~~~~~~ kernel/sched/core.c: In function 'sched_free_group': kernel/sched/core.c:9359:2: error: implicit declaration of function 'sched_core_cgroup_free'; did you mean 'sched_core_free'? [-Werror=implicit-function-declaration] 9359 | sched_core_cgroup_free(tg); | ^~~~~~~~~~~~~~~~~~~~~~ | sched_core_free kernel/sched/core.c: In function 'sched_online_group': kernel/sched/core.c:9404:2: error: implicit declaration of function 'sched_core_cgroup_online' [-Werror=implicit-function-declaration] 9404 | sched_core_cgroup_online(parent, tg); | ^~~~~~~~~~~~~~~~~~~~~~~~ kernel/sched/core.c: In function 'sched_move_task': kernel/sched/core.c:9497:11: error: implicit declaration of function 'sched_core_cgroup_cookie' [-Werror=implicit-function-declaration] 9497 | cookie = sched_core_cgroup_cookie(tsk->sched_task_group); | ^~~~~~~~~~~~~~~~~~~~~~~~ kernel/sched/core.c:9498:11: error: implicit declaration of function 'sched_core_update_cookie' [-Werror=implicit-function-declaration] 9498 | cookie = sched_core_update_cookie(tsk, cookie | GROUP_COOKIE); | ^~~~~~~~~~~~~~~~~~~~~~~~ 9498 | cookie = sched_core_update_cookie(tsk, cookie | GROUP_COOKIE); | ^~~~~~~~~~~~ | SO_COOKIE kernel/sched/core.c:9498:50: note: each undeclared identifier is reported only once for each function it appears in kernel/sched/core.c:9499:2: error: implicit declaration of function 'sched_core_put_cookie' [-Werror=implicit-function-declaration] 9499 | sched_core_put_cookie(cookie); | ^~~~~~~~~~~~~~~~~~~~~ cc1: some warnings being treated as errors vim +9498 kernel/sched/core.c 9454 9455 /* 9456 * Change task's runqueue when it moves between groups. 9457 * 9458 * The caller of this function should have put the task in its new group by 9459 * now. This function just updates tsk->se.cfs_rq and tsk->se.parent to reflect 9460 * its new group. 9461 */ 9462 void sched_move_task(struct task_struct *tsk) 9463 { 9464 int queued, running, queue_flags = 9465 DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK; 9466 unsigned long cookie; 9467 struct rq_flags rf; 9468 struct rq *rq; 9469 9470 rq = task_rq_lock(tsk, &rf); 9471 update_rq_clock(rq); 9472 9473 running = task_current(rq, tsk); 9474 queued = task_on_rq_queued(tsk); 9475 9476 if (queued) 9477 dequeue_task(rq, tsk, queue_flags); 9478 if (running) 9479 put_prev_task(rq, tsk); 9480 9481 sched_change_group(tsk, TASK_MOVE_GROUP); 9482 9483 if (queued) 9484 enqueue_task(rq, tsk, queue_flags); 9485 if (running) { 9486 set_next_task(rq, tsk); 9487 /* 9488 * After changing group, the running task may have joined a 9489 * throttled one but it's still the running task. Trigger a 9490 * resched to make sure that task can still run. 9491 */ 9492 resched_curr(rq); 9493 } 9494 9495 task_rq_unlock(rq, tsk, &rf); 9496 9497 cookie = sched_core_cgroup_cookie(tsk->sched_task_group); 9499 sched_core_put_cookie(cookie); 9500 } 9501 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org