tree: https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git sched/core head: e337f389dc4d3748ba4342bd2d1c2133346b8691 commit: 92318ca36a5876d444849ea850534488e843f077 [2/4] sched/hotplug: Ensure only per-cpu kthreads run during hotplug config: x86_64-randconfig-s022-20200914 (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.2-191-g10164920-dirty git checkout 92318ca36a5876d444849ea850534488e843f077 # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; sparse warnings: (new ones prefixed by >>) kernel/sched/core.c:610:38: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct task_struct *curr @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/core.c:610:38: sparse: expected struct task_struct *curr kernel/sched/core.c:610:38: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/core.c:1697:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/core.c:1697:33: sparse: expected struct task_struct *p kernel/sched/core.c:1697:33: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/core.c:1697:68: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *tsk @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/core.c:1697:68: sparse: expected struct task_struct *tsk kernel/sched/core.c:1697:68: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/core.c:2439:17: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct sched_domain *[assigned] sd @@ got struct sched_domain [noderef] __rcu *parent @@ kernel/sched/core.c:2439:17: sparse: expected struct sched_domain *[assigned] sd kernel/sched/core.c:2439:17: sparse: got struct sched_domain [noderef] __rcu *parent kernel/sched/core.c:2631:36: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct const *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/core.c:2631:36: sparse: expected struct task_struct const *p kernel/sched/core.c:2631:36: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/core.c:6883:43: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/core.c:4026:38: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct task_struct *curr @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/core.c:4026:38: sparse: expected struct task_struct *curr kernel/sched/core.c:4026:38: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/core.c:4459:14: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct task_struct *prev @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/core.c:4459:14: sparse: expected struct task_struct *prev kernel/sched/core.c:4459:14: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/core.c:4922:17: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/core.c:4922:17: sparse: struct task_struct * kernel/sched/core.c:4922:17: sparse: struct task_struct [noderef] __rcu * kernel/sched/core.c:5124:22: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/core.c:5124:22: sparse: struct task_struct [noderef] __rcu * kernel/sched/core.c:5124:22: sparse: struct task_struct * kernel/sched/core.c:8019:11: sparse: sparse: symbol 'max_cfs_quota_period' was not declared. Should it be static? kernel/sched/core.c:8570:25: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/core.c:8570:25: sparse: expected struct task_struct *p kernel/sched/core.c:8570:25: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/core.c: note: in included file: kernel/sched/pelt.h:85:13: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct const *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/pelt.h:85:13: sparse: expected struct task_struct const *p kernel/sched/pelt.h:85:13: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/core.c:1688:33: sparse: sparse: dereference of noderef expression kernel/sched/core.c:1689:19: sparse: sparse: dereference of noderef expression kernel/sched/core.c:1690:37: sparse: sparse: dereference of noderef expression kernel/sched/core.c: note: in included file: kernel/sched/sched.h:1695:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1695:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1695:25: sparse: struct task_struct * kernel/sched/sched.h:1840:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1840:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1840:9: sparse: struct task_struct * kernel/sched/sched.h:1846:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1846:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1846:9: sparse: struct task_struct * kernel/sched/core.c:1663:38: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/core.c:1663:38: sparse: struct task_struct [noderef] __rcu * kernel/sched/core.c:1663:38: sparse: struct task_struct const * kernel/sched/sched.h:1695:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1695:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1695:25: sparse: struct task_struct * kernel/sched/sched.h:1840:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1840:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1840:9: sparse: struct task_struct * kernel/sched/sched.h:1840:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1840:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1840:9: sparse: struct task_struct * kernel/sched/sched.h:1695:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1695:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1695:25: sparse: struct task_struct * kernel/sched/sched.h:1840:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1840:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1840:9: sparse: struct task_struct * kernel/sched/sched.h:1846:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1846:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1846:9: sparse: struct task_struct * kernel/sched/sched.h:1695:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1695:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1695:25: sparse: struct task_struct * kernel/sched/sched.h:1840:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1840:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1840:9: sparse: struct task_struct * kernel/sched/sched.h:1846:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1846:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1846:9: sparse: struct task_struct * kernel/sched/sched.h:1695:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1695:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1695:25: sparse: struct task_struct * kernel/sched/sched.h:1840:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1840:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1840:9: sparse: struct task_struct * kernel/sched/sched.h:1846:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1846:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1846:9: sparse: struct task_struct * kernel/sched/sched.h:1695:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1695:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1695:25: sparse: struct task_struct * kernel/sched/sched.h:1840:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1840:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1840:9: sparse: struct task_struct * kernel/sched/sched.h:1846:9: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1846:9: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1846:9: sparse: struct task_struct * # 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 git checkout 92318ca36a5876d444849ea850534488e843f077 vim +6883 kernel/sched/core.c 6877 6878 /* 6879 * Ensure we only run per-cpu kthreads once the CPU goes !active. 6880 */ 6881 static bool balance_push(struct rq *rq) 6882 { 6884 6885 lockdep_assert_held(&rq->lock); 6886 SCHED_WARN_ON(rq->cpu != smp_processor_id()); 6887 6888 /* 6889 * Both the cpu-hotplug and stop task are in this case and are 6890 * required to complete the hotplug process. 6891 */ 6892 if (is_per_cpu_kthread(push_task)) 6893 return false; 6894 6895 get_task_struct(push_task); 6896 /* 6897 * Temporarily drop rq->lock such that we can wake-up the stop task. 6898 * Both preemption and IRQs are still disabled. 6899 */ 6900 raw_spin_unlock(&rq->lock); 6901 stop_one_cpu_nowait(rq->cpu, __balance_push_cpu_stop, push_task, 6902 this_cpu_ptr(&push_work)); 6903 /* 6904 * At this point need_resched() is true and we'll take the loop in 6905 * schedule(). The next pick is obviously going to be the stop task 6906 * which is_per_cpu_kthread() and will push this task away. 6907 */ 6908 raw_spin_lock(&rq->lock); 6909 6910 return true; 6911 } 6912 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org