INFO: task syz-executor671:30173 can't die for more than 143 seconds. syz-executor671 D28160 30173 8924 0x00004004 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x8e1/0x1f30 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 schedule_timeout+0x717/0xc50 kernel/time/timer.c:1871 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 io_wq_destroy+0x22a/0x450 fs/io-wq.c:1068 io_finish_async+0x128/0x1b0 fs/io_uring.c:3423 io_ring_ctx_free fs/io_uring.c:4220 [inline] io_ring_ctx_wait_and_kill+0x2b7/0x810 fs/io_uring.c:4293 io_uring_release+0x42/0x50 fs/io_uring.c:4301 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x676/0x790 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x401f90 Code: 01 f0 ff ff 0f 83 40 0d 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d fd 9f 2d 00 00 75 14 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 14 0d 00 00 c3 48 83 ec 08 e8 7a 02 00 00 RSP: 002b:00007ffc5e476338 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000401f90 RDX: 0000000000401f30 RSI: 0000000020002740 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000392 R13: 0000000000000003 R14: 0000000000000004 R15: 0000000000000000 INFO: task syz-executor671:30173 blocked for more than 143 seconds. Not tainted 5.4.0-rc7-next-20191115 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor671 D28160 30173 8924 0x00004004 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x8e1/0x1f30 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 schedule_timeout+0x717/0xc50 kernel/time/timer.c:1871 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 io_wq_destroy+0x22a/0x450 fs/io-wq.c:1068 io_finish_async+0x128/0x1b0 fs/io_uring.c:3423 io_ring_ctx_free fs/io_uring.c:4220 [inline] io_ring_ctx_wait_and_kill+0x2b7/0x810 fs/io_uring.c:4293 io_uring_release+0x42/0x50 fs/io_uring.c:4301 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x676/0x790 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x401f90 Code: 01 f0 ff ff 0f 83 40 0d 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d fd 9f 2d 00 00 75 14 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 14 0d 00 00 c3 48 83 ec 08 e8 7a 02 00 00 RSP: 002b:00007ffc5e476338 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000401f90 RDX: 0000000000401f30 RSI: 0000000020002740 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000392 R13: 0000000000000003 R14: 0000000000000004 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1079: #0: ffffffff88faccc0 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5334 3 locks held by kworker/1:2/3614: #0: ffff8880ae937358 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1215 [inline] #0: ffff8880ae937358 (&rq->lock){-.-.}, at: __schedule+0x232/0x1f30 kernel/sched/core.c:4029 #1: ffffffff88faccc0 (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:435 [inline] #1: ffffffff88faccc0 (rcu_read_lock){....}, at: update_curr+0x2ea/0x8d0 kernel/sched/fair.c:859 #2: ffff8880ae928318 (&base->lock){-.-.}, at: lock_timer_base+0x56/0x1b0 kernel/time/timer.c:936 2 locks held by getty/8892: #0: ffff8880a18f4090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8893: #0: ffff8880a8b93090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f152e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8894: #0: ffff8880a0439090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8895: #0: ffff888092e65090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f352e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8896: #0: ffff8880a7e3f090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f392e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8897: #0: ffff8880a9029090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f2d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8898: #0: ffff8880a04da090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f092e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1079 Comm: khungtaskd Not tainted 5.4.0-rc7-next-20191115 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:269 [inline] watchdog+0xc8f/0x1350 kernel/hung_task.c:353 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8923 Comm: syz-executor671 Not tainted 5.4.0-rc7-next-20191115 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_memory_region_inline mm/kasan/generic.c:176 [inline] RIP: 0010:check_memory_region+0x22/0x1a0 mm/kasan/generic.c:192 Code: 0f 1f 84 00 00 00 00 00 48 85 f6 0f 84 34 01 00 00 48 b8 ff ff ff ff ff 7f ff ff 55 0f b6 d2 48 39 c7 48 89 e5 41 55 41 54 53 <0f> 86 07 01 00 00 4c 8d 5c 37 ff 49 89 f8 48 b8 00 00 00 00 00 fc RSP: 0018:ffff8880999bfec0 EFLAGS: 00000012 RAX: ffff7fffffffffff RBX: ffff8880950a8200 RCX: ffffffff812a4ce4 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8880950a8200 RBP: ffff8880999bfed8 R08: ffff8880950a8200 R09: ffffed1012a15041 R10: ffffed1012a15040 R11: ffff8880950a8207 R12: ffff8880950a8200 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 000000000149c880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020002740 CR3: 000000008e557000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __kasan_check_read+0x11/0x20 mm/kasan/common.c:94 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline] test_ti_thread_flag include/linux/thread_info.h:84 [inline] fpregs_assert_state_consistent+0x24/0xf0 arch/x86/kernel/fpu/core.c:357 prepare_exit_to_usermode arch/x86/entry/common.c:203 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x3ac/0x790 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x40217a Code: c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 8b 05 1e 9e 2d 00 85 c0 75 36 45 31 d2 48 63 d2 48 63 ff b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 d0 ff ff ff f7 RSP: 002b:00007ffc5e476338 EFLAGS: 00000246 ORIG_RAX: 000000000000003d RAX: 0000000000000000 RBX: 0000000000129d8d RCX: 000000000040217a RDX: 0000000040000001 RSI: 00007ffc5e47634c RDI: ffffffffffffffff RBP: 0000000000000d53 R08: 0000000000000001 R09: 000000000149c880 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000d51 R13: 0000000000000003 R14: 0000000000000004 R15: 0000000000000000