syzbot


INFO: rcu detected stall in futex_wake

Status: closed as invalid on 2018/06/27 15:08
Subsystems: kernel
[Documentation on labels]
First crash: 2687d, last: 2687d

Sample crash report:
INFO: rcu_sched detected stalls on CPUs/tasks:
	(detected by 1, t=120002 jiffies, g=14729, c=14728, q=552)
All QSes seen, last rcu_sched kthread activity 120002 (4294874770-4294754768), jiffies_till_next_fqs=3, root ->qsmask 0x0
syz-executor7   R  running task    59968  6874   4566 0x00000008
Call Trace:
 <IRQ>
 sched_show_task+0x600/0x730 kernel/sched/core.c:5279
 print_other_cpu_stall kernel/rcu/tree.c:1480 [inline]
 check_cpu_stall kernel/rcu/tree.c:1598 [inline]
 __rcu_pending kernel/rcu/tree.c:3361 [inline]
 rcu_pending kernel/rcu/tree.c:3423 [inline]
 rcu_check_callbacks+0x292f/0x2cd0 kernel/rcu/tree.c:2763
 update_process_times+0x132/0x1a0 kernel/time/timer.c:1636
 tick_sched_handle kernel/time/tick-sched.c:162 [inline]
 tick_sched_timer+0x33b/0x4b0 kernel/time/tick-sched.c:1194
 __run_hrtimer kernel/time/hrtimer.c:1349 [inline]
 __hrtimer_run_queues+0xc03/0x15d0 kernel/time/hrtimer.c:1411
 hrtimer_interrupt+0x426/0xaf0 kernel/time/hrtimer.c:1469
 local_apic_timer_interrupt+0x66/0x230 arch/x86/kernel/apic/apic.c:1025
 smp_apic_timer_interrupt+0x5a/0x90 arch/x86/kernel/apic/apic.c:1053
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:857
 </IRQ>
RIP: 0010:rep_nop arch/x86/include/asm/processor.h:657 [inline]
RIP: 0010:cpu_relax arch/x86/include/asm/processor.h:662 [inline]
RIP: 0010:queued_spin_lock_slowpath+0x522/0xab0 kernel/locking/qspinlock.c:362
RSP: 0018:ffff88015254f8b0 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff12
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffc90000c65a2e
RDX: ffffffff8b311000 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffff88015254f930 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000000 R14: 00000000000000ff R15: ffffc90000c65a04
 queued_spin_lock include/asm-generic/qspinlock.h:90 [inline]
 do_raw_spin_lock include/linux/spinlock.h:161 [inline]
 __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_lock+0x79/0x80 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:310 [inline]
 futex_wake+0x232/0xba0 kernel/futex.c:1536
 do_futex+0x28d1/0x6ad0 kernel/futex.c:3531
 SYSC_futex+0x3e1/0x810 kernel/futex.c:3587
 SyS_futex+0x89/0xb0 kernel/futex.c:3555
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x455389
RSP: 002b:0000000000a3e8e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 000000000072bf58 RCX: 0000000000455389
RDX: ffffffffffffffff RSI: 0000000000000001 RDI: 000000000072bf84
RBP: 0000000000000462 R08: 0000000000a3ea30 R09: 000000000072bf58
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000a3ea30 R14: 000000000072bf84 R15: 0000000000000001
rcu_sched kthread starved for 120002 jiffies! g14729 c14728 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0
rcu_sched       R  running task    61968     8      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2866 [inline]
 __schedule+0x674/0x730 kernel/sched/core.c:3446
 schedule+0x1cc/0x2f0 kernel/sched/core.c:3505
 schedule_timeout+0x3e7/0x570 kernel/time/timer.c:1801
 rcu_gp_kthread+0x21e1/0x38d0 kernel/rcu/tree.c:2230
 kthread+0x539/0x720 kernel/kthread.c:239
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:406

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/04/25 07:41 https://github.com/google/kmsan.git master d2d741e5d189 37e76fe2 .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.