tree: https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git sched/wip2 head: d30dd3f16ed52ccc4d9abe60d4c7bde2159bf4b3 commit: 654d4f9b26bf733bc9eddf18dd584ed5869ee307 [15/16] sched: Fix migrate_disable() vs rt/dl balancing :::::: branch date: 4 hours ago :::::: commit date: 4 hours ago config: i386-randconfig-s001-20201003 (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.2-201-g24bdaac6-dirty # 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/wip2 git checkout 654d4f9b26bf733bc9eddf18dd584ed5869ee307 # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; echo echo "sparse warnings: (new ones prefixed by >>)" echo kernel/sched/rt.c:912:70: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/rt.c:912:70: sparse: struct task_struct [noderef] __rcu * kernel/sched/rt.c:912:70: sparse: struct task_struct * kernel/sched/rt.c:2211:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/rt.c:2211:25: sparse: struct task_struct * kernel/sched/rt.c:2211:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/rt.c:529:54: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct task_struct *curr @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/rt.c:529:54: sparse: expected struct task_struct *curr kernel/sched/rt.c:529:54: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/rt.c:998:38: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct task_struct *curr @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/rt.c:998:38: sparse: expected struct task_struct *curr kernel/sched/rt.c:998:38: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/rt.c:1424:31: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected struct task_struct *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/rt.c:1424:31: sparse: expected struct task_struct *p kernel/sched/rt.c:1424:31: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/rt.c:1741:9: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct sched_domain *[assigned] sd @@ got struct sched_domain [noderef] __rcu *parent @@ kernel/sched/rt.c:1741:9: sparse: expected struct sched_domain *[assigned] sd kernel/sched/rt.c:1741:9: sparse: got struct sched_domain [noderef] __rcu *parent kernel/sched/rt.c:1444:14: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct task_struct *curr @@ got struct task_struct [noderef] __rcu *const volatile @@ kernel/sched/rt.c:1444:14: sparse: expected struct task_struct *curr kernel/sched/rt.c:1444:14: sparse: got struct task_struct [noderef] __rcu *const volatile kernel/sched/rt.c:1509:45: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected struct task_struct *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/rt.c:1509:45: sparse: expected struct task_struct *p kernel/sched/rt.c:1509:45: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/rt.c:1570:67: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *tsk @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/rt.c:1570:67: sparse: expected struct task_struct *tsk kernel/sched/rt.c:1570:67: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/rt.c:1883:40: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *task @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/rt.c:1883:40: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/rt.c:1904:13: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/rt.c:1904:13: sparse: struct task_struct * kernel/sched/rt.c:1904:13: sparse: struct task_struct [noderef] __rcu * kernel/sched/rt.c:2262:54: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *tsk @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/rt.c:2262:54: sparse: expected struct task_struct *tsk kernel/sched/rt.c:2262:54: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/rt.c:2264:40: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/rt.c:2264:40: sparse: expected struct task_struct *p kernel/sched/rt.c:2264:40: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/rt.c:2264:61: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/rt.c:2264:61: sparse: expected struct task_struct *p kernel/sched/rt.c:2264:61: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/rt.c:2335:46: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/rt.c:2335:46: sparse: struct task_struct [noderef] __rcu * kernel/sched/rt.c:2335:46: sparse: struct task_struct * kernel/sched/rt.c:2355:22: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/rt.c:2355:22: sparse: struct task_struct [noderef] __rcu * kernel/sched/rt.c:2355:22: sparse: struct task_struct * kernel/sched/rt.c: note: in included file: kernel/sched/sched.h:1716:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1716:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1716:25: sparse: struct task_struct * kernel/sched/sched.h:1716:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/sched.h:1716:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/sched.h:1716:25: sparse: struct task_struct * vim +1883 kernel/sched/rt.c 917b627d4d981dc kernel/sched_rt.c Gregory Haskins 2008-12-29 1856 e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1857 /* e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1858 * If the current CPU has more than one RT task, see if the non e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1859 * running task can migrate over to a CPU that is running a task e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1860 * of lesser priority. e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1861 */ 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1862 static int push_rt_task(struct rq *rq, bool pull) e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1863 { e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1864 struct task_struct *next_task; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1865 struct rq *lowest_rq; 311e800e16f63d9 kernel/sched_rt.c Hillf Danton 2011-06-16 1866 int ret = 0; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1867 a22d7fc187ed996 kernel/sched_rt.c Gregory Haskins 2008-01-25 1868 if (!rq->rt.overloaded) a22d7fc187ed996 kernel/sched_rt.c Gregory Haskins 2008-01-25 1869 return 0; a22d7fc187ed996 kernel/sched_rt.c Gregory Haskins 2008-01-25 1870 917b627d4d981dc kernel/sched_rt.c Gregory Haskins 2008-12-29 1871 next_task = pick_next_pushable_task(rq); e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1872 if (!next_task) e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1873 return 0; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1874 e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1875 retry: 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1876 if (is_migration_disabled(next_task)) { 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1877 struct task_struct *push_task = NULL; 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1878 int cpu; 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1879 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1880 if (!pull || rq->push_busy) 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1881 return 0; 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1882 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 @1883 cpu = find_lowest_rq(rq->curr); 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1884 if (cpu == -1 || cpu == rq->cpu) 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1885 return 0; 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1886 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1887 /* 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1888 * Given we found a CPU with lower priority than @next_task, 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1889 * therefore it should be running. However we cannot migrate it 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1890 * to this other CPU, instead attempt to push the current 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1891 * running task on this CPU away. 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1892 */ 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1893 push_task = get_push_task(rq); 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1894 if (push_task) { 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1895 raw_spin_unlock(&rq->lock); 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1896 stop_one_cpu_nowait(rq->cpu, push_cpu_stop, 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1897 push_task, &rq->push_work); 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1898 raw_spin_lock(&rq->lock); 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1899 } 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1900 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1901 return 0; 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1902 } 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1903 9ebc6053814d37b kernel/sched/rt.c Yangtao Li 2018-11-03 1904 if (WARN_ON(next_task == rq->curr)) e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1905 return 0; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1906 e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1907 /* e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1908 * It's possible that the next_task slipped in of e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1909 * higher priority than current. If that's the case e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1910 * just reschedule current. e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1911 */ 697f0a487f294e6 kernel/sched_rt.c Gregory Haskins 2008-01-25 1912 if (unlikely(next_task->prio < rq->curr->prio)) { 8875125efe8402c kernel/sched/rt.c Kirill Tkhai 2014-06-29 1913 resched_curr(rq); e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1914 return 0; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1915 } e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1916 697f0a487f294e6 kernel/sched_rt.c Gregory Haskins 2008-01-25 1917 /* We might release rq lock */ e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1918 get_task_struct(next_task); e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1919 e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1920 /* find_lock_lowest_rq locks the rq if found */ 697f0a487f294e6 kernel/sched_rt.c Gregory Haskins 2008-01-25 1921 lowest_rq = find_lock_lowest_rq(next_task, rq); e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1922 if (!lowest_rq) { e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1923 struct task_struct *task; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1924 /* 311e800e16f63d9 kernel/sched_rt.c Hillf Danton 2011-06-16 1925 * find_lock_lowest_rq releases rq->lock 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1926 * so it is possible that next_task has migrated. 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1927 * 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1928 * We need to make sure that the task is still on the same 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1929 * run-queue and is also still the next task eligible for 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1930 * pushing. e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1931 */ 917b627d4d981dc kernel/sched_rt.c Gregory Haskins 2008-12-29 1932 task = pick_next_pushable_task(rq); de16b91effdbf5a kernel/sched/rt.c Byungchul Park 2017-05-12 1933 if (task == next_task) { 917b627d4d981dc kernel/sched_rt.c Gregory Haskins 2008-12-29 1934 /* 311e800e16f63d9 kernel/sched_rt.c Hillf Danton 2011-06-16 1935 * The task hasn't migrated, and is still the next 311e800e16f63d9 kernel/sched_rt.c Hillf Danton 2011-06-16 1936 * eligible task, but we failed to find a run-queue 311e800e16f63d9 kernel/sched_rt.c Hillf Danton 2011-06-16 1937 * to push it to. Do not retry in this case, since 97fb7a0a8944bd6 kernel/sched/rt.c Ingo Molnar 2018-03-03 1938 * other CPUs will pull from us when ready. 917b627d4d981dc kernel/sched_rt.c Gregory Haskins 2008-12-29 1939 */ e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1940 goto out; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1941 } e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1942 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1943 if (!task) 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1944 /* No more tasks, just exit */ 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1945 goto out; 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1946 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1947 /* 1563513d34ed4b1 kernel/sched_rt.c Gregory Haskins 2008-12-29 1948 * Something has shifted, try again. e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1949 */ e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1950 put_task_struct(next_task); e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1951 next_task = task; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1952 goto retry; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1953 } e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1954 697f0a487f294e6 kernel/sched_rt.c Gregory Haskins 2008-01-25 1955 deactivate_task(rq, next_task, 0); e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1956 set_task_cpu(next_task, lowest_rq->cpu); e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1957 activate_task(lowest_rq, next_task, 0); 8875125efe8402c kernel/sched/rt.c Kirill Tkhai 2014-06-29 1958 resched_curr(lowest_rq); 654d4f9b26bf733 kernel/sched/rt.c Peter Zijlstra 2020-09-28 1959 ret = 1; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1960 1b12bbc747560ea kernel/sched_rt.c Peter Zijlstra 2008-08-11 1961 double_unlock_balance(rq, lowest_rq); e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1962 out: e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1963 put_task_struct(next_task); e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1964 311e800e16f63d9 kernel/sched_rt.c Hillf Danton 2011-06-16 1965 return ret; e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1966 } e8fa136262e1121 kernel/sched_rt.c Steven Rostedt 2008-01-25 1967 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org