kobject: 'loop1' (ffff8880a40f2c20): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop1' (ffff8880a40f2c20): kobject_uevent_env kobject: 'loop1' (ffff8880a40f2c20): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop5' (ffff8880a422d660): kobject_uevent_env kobject: 'loop5' (ffff8880a422d660): fill_kobj_path: path = '/devices/virtual/block/loop5' INFO: task syz-executor.3:16346 blocked for more than 140 seconds. Not tainted 4.14.163-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28528 16346 9273 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 fb_release+0x55/0x150 drivers/video/fbdev/core/fbmem.c:1497 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1da/0x220 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x414ae1 RSP: 002b:00007ffde431c4b0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000414ae1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 0000000000000001 R08: ffffffff812aed7d R09: 00000000dbed58ec R10: 00007ffde431c590 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 0000000000760ff0 R15: 000000000075bf2c Showing all locks held in the system: 1 lock held by khungtaskd/1056: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544 1 lock held by rsyslogd/7097: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xab/0xd0 fs/file.c:769 2 locks held by getty/7220: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7221: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7222: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7223: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7224: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7225: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7226: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.3/16346: #0: (&fb_info->lock){+.+.}, at: [] fb_release+0x55/0x150 drivers/video/fbdev/core/fbmem.c:1497 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1056 Comm: khungtaskd Not tainted 4.14.163-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x142/0x197 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x141/0x189 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:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5e7/0xb90 kernel/hung_task.c:274 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 16350 Comm: syz-executor.4 Not tainted 4.14.163-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff88804e5e01c0 task.stack: ffff8881a1040000 RIP: 0010:match_held_lock+0x2d5/0x5f0 kernel/locking/lockdep.c:3586 RSP: 0018:ffff8880aed075b8 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff88804e5e0a40 RCX: ffff88804e5e0a40 RDX: 0000000000000000 RSI: ffffffff87f88620 RDI: ffff88804e5e0a62 RBP: ffff8880aed07630 R08: 1ffff11008d40b84 R09: ffffed1008d40b8b R10: ffffed1008d40b8a R11: ffff888046a05c57 R12: 0000000000000000 R13: 1ffff11015da0eb9 R14: ffffffff87f88620 R15: ffff8880aed07608 FS: 00007fe609686700(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c433c34780 CR3: 000000020e1a4000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_is_held+0xb6/0x140 kernel/locking/lockdep.c:3814 lock_is_held_type+0x110/0x210 kernel/locking/lockdep.c:4032 lock_is_held include/linux/lockdep.h:437 [inline] rcu_read_lock_sched_held+0x110/0x130 kernel/rcu/update.c:116 trace_consume_skb include/trace/events/skb.h:37 [inline] trace_consume_skb include/trace/events/skb.h:37 [inline] consume_skb+0x276/0x340 net/core/skbuff.c:704 sctp_chunk_destroy net/sctp/sm_make_chunk.c:1442 [inline] sctp_chunk_put+0x179/0x270 net/sctp/sm_make_chunk.c:1469 sctp_chunk_free+0x56/0x70 net/sctp/sm_make_chunk.c:1456 sctp_packet_pack net/sctp/output.c:485 [inline] sctp_packet_transmit+0x113f/0x3010 net/sctp/output.c:605 sctp_outq_flush+0xd13/0x31b0 net/sctp/outqueue.c:1187 sctp_outq_uncork+0x60/0x70 net/sctp/outqueue.c:761 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1776 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1179 [inline] sctp_do_sm+0x417/0x4ae0 net/sctp/sm_sideeffect.c:1150 sctp_generate_heartbeat_event+0x1dd/0x400 net/sctp/sm_sideeffect.c:391 call_timer_fn+0x161/0x670 kernel/time/timer.c:1279 expire_timers kernel/time/timer.c:1318 [inline] __run_timers kernel/time/timer.c:1636 [inline] __run_timers kernel/time/timer.c:1604 [inline] run_timer_softirq+0x5b7/0x1520 kernel/time/timer.c:1649 __do_softirq+0x244/0x9a0 kernel/softirq.c:288 invoke_softirq kernel/softirq.c:368 [inline] irq_exit+0x160/0x1b0 kernel/softirq.c:409 exiting_irq arch/x86/include/asm/apic.h:648 [inline] smp_apic_timer_interrupt+0x146/0x5e0 arch/x86/kernel/apic/apic.c:1102 apic_timer_interrupt+0x96/0xa0 arch/x86/entry/entry_64.S:792 RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x1d/0x60 kernel/kcov.c:67 RSP: 0018:ffff8881a1047208 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10 RAX: ffff88804e5e01c0 RBX: 0000000000001400 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff8880000a0000 RDI: ffff8880a5fcc340 RBP: ffff8881a1047248 R08: 0000000000001400 R09: 0000000000000040 R10: ffffed1014be6e43 R11: ffff8880a5f3721f R12: 0000000000000000 R13: 0000000000000000 R14: ffff8880000a0000 R15: 0000000000000000 cfb_fillrect+0x3d0/0x720 drivers/video/fbdev/core/cfbfillrect.c:327 vga16fb_fillrect+0x618/0x1880 drivers/video/fbdev/vga16fb.c:951 bit_clear_margins+0x2d5/0x4f0 drivers/video/fbdev/core/bitblit.c:232 fbcon_clear_margins+0x292/0x320 drivers/video/fbdev/core/fbcon.c:1317 fbcon_switch+0xd38/0x1820 drivers/video/fbdev/core/fbcon.c:2299 redraw_screen+0x335/0x7c0 drivers/tty/vt/vt.c:688 fbcon_modechanged+0x59e/0x880 drivers/video/fbdev/core/fbcon.c:2946 fbcon_set_all_vcs+0x35f/0x420 drivers/video/fbdev/core/fbcon.c:2984 fbcon_event_notify+0x75/0x17af drivers/video/fbdev/core/fbcon.c:3302 notifier_call_chain+0x111/0x1b0 kernel/notifier.c:93 __blocking_notifier_call_chain kernel/notifier.c:317 [inline] __blocking_notifier_call_chain kernel/notifier.c:304 [inline] blocking_notifier_call_chain kernel/notifier.c:328 [inline] blocking_notifier_call_chain+0x80/0xa0 kernel/notifier.c:325 fb_notifier_call_chain+0x25/0x30 drivers/video/fbdev/core/fb_notify.c:45 fb_set_var+0xb09/0xcf0 drivers/video/fbdev/core/fbmem.c:1054 do_fb_ioctl+0x3cc/0x940 drivers/video/fbdev/core/fbmem.c:1127 fb_ioctl+0xe6/0x130 drivers/video/fbdev/core/fbmem.c:1242 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45af49 RSP: 002b:00007fe609685c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045af49 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe6096866d4 R13: 00000000004c3903 R14: 00000000004d9f18 R15: 00000000ffffffff Code: 85 00 03 00 00 44 8b 25 4a 4d 6f 08 45 85 e4 0f 84 7e ec 00 00 45 31 e4 48 b8 00 00 00 00 00 fc ff df 49 c7 44 05 00 00 00 00 00 <48> 83 c4 50 44 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 41 bc 01