Hi Steven, First bad commit (maybe != root cause): tree: https://github.com/zen-kernel/zen-kernel 5.9/muqss head: bb2916b2fc9b8433563583c67044135c9cfad84e commit: bb2916b2fc9b8433563583c67044135c9cfad84e [1/1] Revert "Fix cpufreq_cooling build." config: alpha-randconfig-s031-20201117 (attached as .config) compiler: alpha-linux-gcc (GCC) 9.3.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # apt-get install sparse # sparse version: v0.6.3-107-gaf3512a6-dirty # https://github.com/zen-kernel/zen-kernel/commit/bb2916b2fc9b8433563583c67... git remote add zen-kernel-zen-kernel https://github.com/zen-kernel/zen-kernel git fetch --no-tags zen-kernel-zen-kernel 5.9/muqss git checkout bb2916b2fc9b8433563583c67044135c9cfad84e # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=alpha 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/MuQSS.c:2530:17: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/MuQSS.c:3480:35: sparse: expected struct task_struct *p kernel/sched/MuQSS.c:3480:35: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/MuQSS.c:3712:37: sparse: expected struct task_struct *p kernel/sched/MuQSS.c:3712:37: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/MuQSS.c:4158:14: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/MuQSS.c:4834:22: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/MuQSS.c:4834:22: sparse: struct task_struct [noderef] __rcu * kernel/sched/MuQSS.c:4834:22: sparse: struct task_struct * kernel/sched/MuQSS.c:5847:14: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/MuQSS.c:5855:34: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/MuQSS.c:5855:34: sparse: expected struct task_struct *p kernel/sched/MuQSS.c:5855:34: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/MuQSS.c:6117:25: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/MuQSS.c:6117:25: sparse: expected struct task_struct *p kernel/sched/MuQSS.c:6117:25: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/MuQSS.c:1234:24: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *p @@ got struct task_struct [noderef] __rcu *curr @@ kernel/sched/MuQSS.c:1234:24: sparse: expected struct task_struct *p kernel/sched/MuQSS.c:1234:24: sparse: got struct task_struct [noderef] __rcu *curr kernel/sched/MuQSS.c:1225:27: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/MuQSS.c:1225:27: sparse: struct task_struct [noderef] __rcu * kernel/sched/MuQSS.c:1225:27: sparse: struct task_struct * kernel/sched/MuQSS.c:1225:27: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/MuQSS.c:1225:27: sparse: struct task_struct [noderef] __rcu * kernel/sched/MuQSS.c:1225:27: sparse: struct task_struct * kernel/sched/MuQSS.c:3398:15: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/MuQSS.c:3398:15: sparse: struct task_struct * kernel/sched/MuQSS.c:3398:15: sparse: struct task_struct [noderef] __rcu * kernel/sched/MuQSS.c: note: in included file: kernel/sched/MuQSS.h:382:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/MuQSS.h:382:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/MuQSS.h:382:25: sparse: struct task_struct * kernel/sched/MuQSS.h:382:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/MuQSS.h:382:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/MuQSS.h:382:25: sparse: struct task_struct * kernel/sched/MuQSS.h:382:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/MuQSS.h:382:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/MuQSS.h:382:25: sparse: struct task_struct * kernel/sched/MuQSS.h:382:25: sparse: sparse: incompatible types in comparison expression (different address spaces): kernel/sched/MuQSS.h:382:25: sparse: struct task_struct [noderef] __rcu * kernel/sched/MuQSS.h:382:25: sparse: struct task_struct * vim +2471 kernel/sched/MuQSS.c 49e82d66c704858 Con Kolivas 2019-10-25 2452 49e82d66c704858 Con Kolivas 2019-10-25 2453 /* 49e82d66c704858 Con Kolivas 2019-10-25 2454 * High-resolution time_slice expiry. 49e82d66c704858 Con Kolivas 2019-10-25 2455 * Runs from hardirq context with interrupts disabled. 49e82d66c704858 Con Kolivas 2019-10-25 2456 */ 49e82d66c704858 Con Kolivas 2019-10-25 2457 static enum hrtimer_restart hrexpiry(struct hrtimer *timer) 49e82d66c704858 Con Kolivas 2019-10-25 2458 { 49e82d66c704858 Con Kolivas 2019-10-25 2459 struct rq *rq = container_of(timer, struct rq, hrexpiry_timer); 49e82d66c704858 Con Kolivas 2019-10-25 2460 struct task_struct *p; 49e82d66c704858 Con Kolivas 2019-10-25 2461 49e82d66c704858 Con Kolivas 2019-10-25 2462 /* This can happen during CPU hotplug / resume */ 49e82d66c704858 Con Kolivas 2019-10-25 2463 if (unlikely(cpu_of(rq) != smp_processor_id())) 49e82d66c704858 Con Kolivas 2019-10-25 2464 goto out; 49e82d66c704858 Con Kolivas 2019-10-25 2465 49e82d66c704858 Con Kolivas 2019-10-25 2466 /* 49e82d66c704858 Con Kolivas 2019-10-25 2467 * We're doing this without the runqueue lock but this should always 49e82d66c704858 Con Kolivas 2019-10-25 2468 * be run on the local CPU. Time slice should run out in __schedule 49e82d66c704858 Con Kolivas 2019-10-25 2469 * but we set it to zero here in case niffies is slightly less. 49e82d66c704858 Con Kolivas 2019-10-25 2470 */ 49e82d66c704858 Con Kolivas 2019-10-25 @2471 p = rq->curr; 49e82d66c704858 Con Kolivas 2019-10-25 2472 p->time_slice = 0; 49e82d66c704858 Con Kolivas 2019-10-25 2473 __set_tsk_resched(p); 49e82d66c704858 Con Kolivas 2019-10-25 2474 out: 49e82d66c704858 Con Kolivas 2019-10-25 2475 return HRTIMER_NORESTART; 49e82d66c704858 Con Kolivas 2019-10-25 2476 } 49e82d66c704858 Con Kolivas 2019-10-25 2477 49e82d66c704858 Con Kolivas 2019-10-25 2478 /* 49e82d66c704858 Con Kolivas 2019-10-25 2479 * Called to set the hrexpiry timer state. 49e82d66c704858 Con Kolivas 2019-10-25 2480 * 49e82d66c704858 Con Kolivas 2019-10-25 2481 * called with irqs disabled from the local CPU only 49e82d66c704858 Con Kolivas 2019-10-25 2482 */ 49e82d66c704858 Con Kolivas 2019-10-25 2483 static void hrexpiry_start(struct rq *rq, u64 delay) 49e82d66c704858 Con Kolivas 2019-10-25 2484 { 49e82d66c704858 Con Kolivas 2019-10-25 2485 if (!hrexpiry_enabled(rq)) 49e82d66c704858 Con Kolivas 2019-10-25 2486 return; 49e82d66c704858 Con Kolivas 2019-10-25 2487 49e82d66c704858 Con Kolivas 2019-10-25 2488 hrtimer_start(&rq->hrexpiry_timer, ns_to_ktime(delay), 49e82d66c704858 Con Kolivas 2019-10-25 2489 HRTIMER_MODE_REL_PINNED); 49e82d66c704858 Con Kolivas 2019-10-25 2490 } 49e82d66c704858 Con Kolivas 2019-10-25 2491 49e82d66c704858 Con Kolivas 2019-10-25 2492 static void init_rq_hrexpiry(struct rq *rq) 49e82d66c704858 Con Kolivas 2019-10-25 2493 { 49e82d66c704858 Con Kolivas 2019-10-25 2494 hrtimer_init(&rq->hrexpiry_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 49e82d66c704858 Con Kolivas 2019-10-25 2495 rq->hrexpiry_timer.function = hrexpiry; 49e82d66c704858 Con Kolivas 2019-10-25 2496 } 49e82d66c704858 Con Kolivas 2019-10-25 2497 49e82d66c704858 Con Kolivas 2019-10-25 2498 static inline int rq_dither(struct rq *rq) 49e82d66c704858 Con Kolivas 2019-10-25 2499 { 49e82d66c704858 Con Kolivas 2019-10-25 2500 if (!hrexpiry_enabled(rq)) 49e82d66c704858 Con Kolivas 2019-10-25 2501 return HALF_JIFFY_US; 49e82d66c704858 Con Kolivas 2019-10-25 2502 return 0; 49e82d66c704858 Con Kolivas 2019-10-25 2503 } 49e82d66c704858 Con Kolivas 2019-10-25 2504 49e82d66c704858 Con Kolivas 2019-10-25 2505 /* 49e82d66c704858 Con Kolivas 2019-10-25 2506 * wake_up_new_task - wake up a newly created task for the first time. 49e82d66c704858 Con Kolivas 2019-10-25 2507 * 49e82d66c704858 Con Kolivas 2019-10-25 2508 * This function will do some initial scheduler statistics housekeeping 49e82d66c704858 Con Kolivas 2019-10-25 2509 * that must be done for every newly created context, then puts the task 49e82d66c704858 Con Kolivas 2019-10-25 2510 * on the runqueue and wakes it. 49e82d66c704858 Con Kolivas 2019-10-25 2511 */ 49e82d66c704858 Con Kolivas 2019-10-25 2512 void wake_up_new_task(struct task_struct *p) 49e82d66c704858 Con Kolivas 2019-10-25 2513 { 49e82d66c704858 Con Kolivas 2019-10-25 2514 struct task_struct *parent, *rq_curr; 49e82d66c704858 Con Kolivas 2019-10-25 2515 struct rq *rq, *new_rq; 49e82d66c704858 Con Kolivas 2019-10-25 2516 unsigned long flags; 49e82d66c704858 Con Kolivas 2019-10-25 2517 49e82d66c704858 Con Kolivas 2019-10-25 @2518 parent = p->parent; 49e82d66c704858 Con Kolivas 2019-10-25 2519 49e82d66c704858 Con Kolivas 2019-10-25 2520 raw_spin_lock_irqsave(&p->pi_lock, flags); 49e82d66c704858 Con Kolivas 2019-10-25 2521 p->state = TASK_RUNNING; 49e82d66c704858 Con Kolivas 2019-10-25 2522 /* Task_rq can't change yet on a new task */ 49e82d66c704858 Con Kolivas 2019-10-25 2523 new_rq = rq = task_rq(p); 49e82d66c704858 Con Kolivas 2019-10-25 2524 if (unlikely(needs_other_cpu(p, task_cpu(p)))) { 49e82d66c704858 Con Kolivas 2019-10-25 2525 set_task_cpu(p, valid_task_cpu(p)); 49e82d66c704858 Con Kolivas 2019-10-25 2526 new_rq = task_rq(p); 49e82d66c704858 Con Kolivas 2019-10-25 2527 } 49e82d66c704858 Con Kolivas 2019-10-25 2528 49e82d66c704858 Con Kolivas 2019-10-25 2529 double_rq_lock(rq, new_rq); 49e82d66c704858 Con Kolivas 2019-10-25 @2530 rq_curr = rq->curr; 49e82d66c704858 Con Kolivas 2019-10-25 2531 49e82d66c704858 Con Kolivas 2019-10-25 2532 /* 49e82d66c704858 Con Kolivas 2019-10-25 2533 * Make sure we do not leak PI boosting priority to the child. 49e82d66c704858 Con Kolivas 2019-10-25 2534 */ 49e82d66c704858 Con Kolivas 2019-10-25 2535 p->prio = rq_curr->normal_prio; 49e82d66c704858 Con Kolivas 2019-10-25 2536 49e82d66c704858 Con Kolivas 2019-10-25 2537 trace_sched_wakeup_new(p); 49e82d66c704858 Con Kolivas 2019-10-25 2538 49e82d66c704858 Con Kolivas 2019-10-25 2539 /* 49e82d66c704858 Con Kolivas 2019-10-25 2540 * Share the timeslice between parent and child, thus the 49e82d66c704858 Con Kolivas 2019-10-25 2541 * total amount of pending timeslices in the system doesn't change, 49e82d66c704858 Con Kolivas 2019-10-25 2542 * resulting in more scheduling fairness. If it's negative, it won't 49e82d66c704858 Con Kolivas 2019-10-25 2543 * matter since that's the same as being 0. rq->rq_deadline is only 49e82d66c704858 Con Kolivas 2019-10-25 2544 * modified within schedule() so it is always equal to 49e82d66c704858 Con Kolivas 2019-10-25 2545 * current->deadline. 49e82d66c704858 Con Kolivas 2019-10-25 2546 */ 49e82d66c704858 Con Kolivas 2019-10-25 2547 account_task_cpu(rq, rq_curr); 49e82d66c704858 Con Kolivas 2019-10-25 2548 p->last_ran = rq_curr->last_ran; 49e82d66c704858 Con Kolivas 2019-10-25 2549 if (likely(rq_curr->policy != SCHED_FIFO)) { 49e82d66c704858 Con Kolivas 2019-10-25 2550 rq_curr->time_slice /= 2; 49e82d66c704858 Con Kolivas 2019-10-25 2551 if (rq_curr->time_slice < RESCHED_US) { 49e82d66c704858 Con Kolivas 2019-10-25 2552 /* 49e82d66c704858 Con Kolivas 2019-10-25 2553 * Forking task has run out of timeslice. Reschedule it and 49e82d66c704858 Con Kolivas 2019-10-25 2554 * start its child with a new time slice and deadline. The 49e82d66c704858 Con Kolivas 2019-10-25 2555 * child will end up running first because its deadline will 49e82d66c704858 Con Kolivas 2019-10-25 2556 * be slightly earlier. 49e82d66c704858 Con Kolivas 2019-10-25 2557 */ 49e82d66c704858 Con Kolivas 2019-10-25 2558 __set_tsk_resched(rq_curr); 49e82d66c704858 Con Kolivas 2019-10-25 2559 time_slice_expired(p, new_rq); 49e82d66c704858 Con Kolivas 2019-10-25 2560 if (suitable_idle_cpus(p)) 49e82d66c704858 Con Kolivas 2019-10-25 2561 resched_best_idle(p, task_cpu(p)); 49e82d66c704858 Con Kolivas 2019-10-25 2562 else if (unlikely(rq != new_rq)) 49e82d66c704858 Con Kolivas 2019-10-25 2563 try_preempt(p, new_rq); 49e82d66c704858 Con Kolivas 2019-10-25 2564 } else { 49e82d66c704858 Con Kolivas 2019-10-25 2565 p->time_slice = rq_curr->time_slice; 49e82d66c704858 Con Kolivas 2019-10-25 2566 if (rq_curr == parent && rq == new_rq && !suitable_idle_cpus(p)) { 49e82d66c704858 Con Kolivas 2019-10-25 2567 /* 49e82d66c704858 Con Kolivas 2019-10-25 2568 * The VM isn't cloned, so we're in a good position to 49e82d66c704858 Con Kolivas 2019-10-25 2569 * do child-runs-first in anticipation of an exec. This 49e82d66c704858 Con Kolivas 2019-10-25 2570 * usually avoids a lot of COW overhead. 49e82d66c704858 Con Kolivas 2019-10-25 2571 */ 49e82d66c704858 Con Kolivas 2019-10-25 2572 __set_tsk_resched(rq_curr); 49e82d66c704858 Con Kolivas 2019-10-25 2573 } else { 49e82d66c704858 Con Kolivas 2019-10-25 2574 /* 49e82d66c704858 Con Kolivas 2019-10-25 2575 * Adjust the hrexpiry since rq_curr will keep 49e82d66c704858 Con Kolivas 2019-10-25 2576 * running and its timeslice has been shortened. 49e82d66c704858 Con Kolivas 2019-10-25 2577 */ 49e82d66c704858 Con Kolivas 2019-10-25 2578 hrexpiry_start(rq, US_TO_NS(rq_curr->time_slice)); 49e82d66c704858 Con Kolivas 2019-10-25 2579 try_preempt(p, new_rq); 49e82d66c704858 Con Kolivas 2019-10-25 2580 } 49e82d66c704858 Con Kolivas 2019-10-25 2581 } 49e82d66c704858 Con Kolivas 2019-10-25 2582 } else { 49e82d66c704858 Con Kolivas 2019-10-25 2583 time_slice_expired(p, new_rq); 49e82d66c704858 Con Kolivas 2019-10-25 2584 try_preempt(p, new_rq); 49e82d66c704858 Con Kolivas 2019-10-25 2585 } 49e82d66c704858 Con Kolivas 2019-10-25 2586 activate_task(new_rq, p, 0); 49e82d66c704858 Con Kolivas 2019-10-25 2587 double_rq_unlock(rq, new_rq); 49e82d66c704858 Con Kolivas 2019-10-25 2588 raw_spin_unlock_irqrestore(&p->pi_lock, flags); 49e82d66c704858 Con Kolivas 2019-10-25 2589 } 49e82d66c704858 Con Kolivas 2019-10-25 2590 :::::: The code at line 2471 was first introduced by commit :::::: 49e82d66c704858ba77947984535811593d6dacb MultiQueue Skiplist Scheduler v0.204 :::::: TO: Con Kolivas <kernel(a)kolivas.org&gt; :::::: CC: Con Kolivas <kernel(a)kolivas.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org