kobject: 'loop2' (ffff8880a415f6e0): kobject_uevent_env kobject: 'loop2' (ffff8880a415f6e0): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop3' (ffff8880a41a2620): kobject_uevent_env kobject: 'loop3' (ffff8880a41a2620): fill_kobj_path: path = '/devices/virtual/block/loop3' FAT-fs (loop3): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) INFO: task syz-executor.0:8588 blocked for more than 140 seconds. Not tainted 4.14.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28048 8588 7872 0x80000004 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_timeout+0x93b/0xe10 kernel/time/timer.c:1723 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x160/0x290 kernel/locking/semaphore.c:238 down+0x64/0x90 kernel/locking/semaphore.c:62 console_lock+0x28/0x80 kernel/printk/printk.c:2216 do_con_write.part.0+0x8e/0x1b50 drivers/tty/vt/vt.c:2210 do_con_write drivers/tty/vt/vt.c:2205 [inline] con_write+0x38/0xc0 drivers/tty/vt/vt.c:2787 process_output_block drivers/tty/n_tty.c:595 [inline] n_tty_write+0x38b/0xf20 drivers/tty/n_tty.c:2333 do_tty_write drivers/tty/tty_io.c:959 [inline] tty_write+0x3f6/0x700 drivers/tty/tty_io.c:1043 __vfs_write+0x105/0x6b0 fs/read_write.c:480 __kernel_write+0xfc/0x370 fs/read_write.c:501 write_pipe_buf+0x148/0x1c0 fs/splice.c:797 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x348/0x780 fs/splice.c:626 splice_from_pipe+0xf0/0x150 fs/splice.c:661 default_file_splice_write+0x3c/0x80 fs/splice.c:809 do_splice_from fs/splice.c:851 [inline] direct_splice_actor+0x123/0x190 fs/splice.c:1018 splice_direct_to_actor+0x29e/0x7b0 fs/splice.c:973 do_splice_direct+0x18d/0x230 fs/splice.c:1061 do_sendfile+0x4db/0xbd0 fs/read_write.c:1441 SYSC_sendfile64 fs/read_write.c:1502 [inline] SyS_sendfile64+0x102/0x110 fs/read_write.c:1488 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45a919 RSP: 002b:00007f642ef0ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045a919 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0c0000008000000b R11: 0000000000000246 R12: 00007f642ef0f6d4 R13: 00000000004c925e R14: 00000000004e0f88 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1046: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544 1 lock held by rsyslogd/6847: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xab/0xd0 fs/file.c:769 2 locks held by getty/6969: #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/6970: #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/6971: #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/6972: #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/6973: #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/6974: #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/6975: #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 4 locks held by syz-executor.0/8588: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&tty->atomic_write_lock){+.+.}, at: [] tty_write_lock+0x20/0x60 drivers/tty/tty_io.c:885 #2: (&tty->termios_rwsem){++++}, at: [] n_tty_write+0x179/0xf20 drivers/tty/n_tty.c:2316 #3: (&ldata->output_lock){+.+.}, at: [] process_output_block drivers/tty/n_tty.c:550 [inline] #3: (&ldata->output_lock){+.+.}, at: [] n_tty_write+0x48a/0xf20 drivers/tty/n_tty.c:2333 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1046 Comm: khungtaskd Not tainted 4.14.160-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: 8561 Comm: syz-executor.4 Not tainted 4.14.160-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880484d6580 task.stack: ffff8880485c0000 RIP: 0010:__sanitizer_cov_trace_pc+0x41/0x60 kernel/kcov.c:87 RSP: 0018:ffff8880485c7320 EFLAGS: 00000246 RAX: 0000000000040000 RBX: ffff8880000a0050 RCX: ffffc9000b447000 RDX: 000000000003ffff RSI: ffffffff832c89a0 RDI: ffff8880485c73f0 RBP: ffff8880485c7320 R08: 00000000fffffe20 R09: ffffed1043246d0c R10: ffffed1043246d0b R11: ffff88821923685f R12: 0000000000000050 R13: 0000000000000000 R14: 00000000dd52341d R15: ffff8880000a004e FS: 00007feb069ac700(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f48ee4265f8 CR3: 000000008d766000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: writeb arch/x86/include/asm/io.h:65 [inline] vga16fb_fillrect+0x940/0x1880 drivers/video/fbdev/vga16fb.c:923 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_event_notify+0x11f/0x17af drivers/video/fbdev/core/fbcon.c:3299 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: 0033:0x45a919 RSP: 002b:00007feb069abc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a919 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000009 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007feb069ac6d4 R13: 00000000004c310d R14: 00000000004d8498 R15: 00000000ffffffff Code: e2 00 01 1f 00 75 0b 8b 90 50 13 00 00 83 fa 01 74 01 c3 55 48 89 e5 48 8b 75 08 48 8b 88 58 13 00 00 8b 80 54 13 00 00 48 8b 11 <48> 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 5d c3 0f 1f 00