INFO: rcu detected stall in snd_seq_oss

Title	Replies (including bot)	Last reply
INFO: rcu detected stall in snd_seq_oss_write	0 (1)	2018/07/30 14:27

INFO: rcu_sched detected stalls on CPUs/tasks: (detected by 1, t=105002 jiffies, g=114619, c=114618, q=1460) All QSes seen, last rcu_sched kthread activity 55292 (4295532443-4295477151), jiffies_till_next_fqs=3, root ->qsmask 0x0 syz-executor3 R running task 21928 9814 4421 0x2002000c Call Trace: <IRQ> sched_show_task.cold.84+0x27a/0x301 kernel/sched/core.c:5324 print_other_cpu_stall.cold.77+0x92f/0x9d2 kernel/rcu/tree.c:1441 check_cpu_stall.isra.60+0x721/0xf70 kernel/rcu/tree.c:1559 __rcu_pending kernel/rcu/tree.c:3244 [inline] rcu_pending kernel/rcu/tree.c:3291 [inline] rcu_check_callbacks+0x23f/0xcd0 kernel/rcu/tree.c:2646 update_process_times+0x2d/0x70 kernel/time/timer.c:1636 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274 __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0x3eb/0x10c0 kernel/time/hrtimer.c:1460 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline] smp_apic_timer_interrupt+0x165/0x730 arch/x86/kernel/apic/apic.c:1050 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863 </IRQ> RIP: 0010:arch_local_irq_disable arch/x86/include/asm/paravirt.h:788 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:801 [inline] RIP: 0010:lock_release+0x13c/0xa30 kernel/locking/lockdep.c:3939 Code: 48 89 85 e8 fe ff ff 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 40 07 00 00 48 83 3d 44 95 92 06 00 <0f> 84 53 06 00 00 fa 66 0f 1f 44 00 00 65 4c 8b 3c 25 40 ee 01 00 RSP: 0018:ffff88019c8ff7f0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 1ffff1003391ff03 RCX: ffffc90005236000 RDX: 1ffffffff0fe3616 RSI: 0000000000000000 RDI: ffffffff87f1b0b0 RBP: ffff88019c8ff920 R08: 0000000000000000 R09: 0000000000000000 R10: ffff88019907c978 R11: b21129c27367def3 R12: ffff88019c8ff8f8 R13: ffff8801abf50bc8 R14: ffff88019c8ffa20 R15: ffff88019907c140 __might_fault+0x19e/0x1e0 mm/memory.c:4564 _copy_from_user+0x30/0x150 lib/usercopy.c:10 copy_from_user include/linux/uaccess.h:147 [inline] snd_seq_oss_write+0x188/0xb70 sound/core/seq/oss/seq_oss_rw.c:106 odev_write+0x59/0x90 sound/core/seq/oss/seq_oss.c:177 __vfs_write+0x117/0x9f0 fs/read_write.c:485 vfs_write+0x1f8/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __ia32_sys_write+0x71/0xb0 fs/read_write.c:607 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f87cb9 Code: 55 08 8b 88 64 cd ff ff 8b 98 68 cd ff ff 89 c8 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 1c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f5f410cc EFLAGS: 00000296 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000020000240 RDX: 00000000fffffe71 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_sched kthread starved for 55292 jiffies! g114619 c114618 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=1 RCU grace-period kthread stack dump: rcu_sched R running task 23688 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 schedule_timeout+0x140/0x260 kernel/time/timer.c:1801 rcu_gp_kthread+0x717/0x1c90 kernel/rcu/tree.c:2179 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412