NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 INFO: task syz-executor.2:23898 blocked for more than 140 seconds. Not tainted 4.14.182-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D27504 23898 6354 0x80000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x8a6/0x1d70 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_timeout+0x86c/0xe50 kernel/time/timer.c:1723 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x17f/0x280 kernel/locking/semaphore.c:238 down+0x57/0x80 kernel/locking/semaphore.c:62 console_lock+0x24/0x70 kernel/printk/printk.c:2216 do_con_write.part.0+0x8c/0x1a20 drivers/tty/vt/vt.c:2223 do_con_write drivers/tty/vt/vt.c:2218 [inline] con_write+0x33/0xc0 drivers/tty/vt/vt.c:2798 process_output_block drivers/tty/n_tty.c:595 [inline] n_tty_write+0x375/0xe20 drivers/tty/n_tty.c:2333 do_tty_write drivers/tty/tty_io.c:959 [inline] tty_write+0x3f1/0x6e0 drivers/tty/tty_io.c:1043 __vfs_write+0xe4/0x630 fs/read_write.c:480 __kernel_write+0xf5/0x330 fs/read_write.c:501 write_pipe_buf+0x143/0x1b0 fs/splice.c:797 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x332/0x740 fs/splice.c:626 splice_from_pipe+0xc6/0x120 fs/splice.c:661 default_file_splice_write+0x37/0x80 fs/splice.c:809 do_splice_from fs/splice.c:851 [inline] direct_splice_actor+0x115/0x160 fs/splice.c:1018 splice_direct_to_actor+0x27e/0x730 fs/splice.c:973 do_splice_direct+0x164/0x210 fs/splice.c:1061 do_sendfile+0x469/0xaf0 fs/read_write.c:1441 SYSC_sendfile64 fs/read_write.c:1502 [inline] SyS_sendfile64+0xff/0x110 fs/read_write.c:1488 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45ca29 RSP: 002b:00007f6a909ddc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00000000004fc540 RCX: 000000000045ca29 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000006 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0800000080004103 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000008dc R14: 00000000004cba16 R15: 00007f6a909de6d4 INFO: task syz-executor.5:23896 blocked for more than 140 seconds. Not tainted 4.14.182-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28816 23896 6353 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x8a6/0x1d70 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x5f0/0x1430 kernel/locking/mutex.c:893 fb_open+0xb7/0x400 drivers/video/fbdev/core/fbmem.c:1468 chrdev_open+0x1fc/0x540 fs/char_dev.c:423 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0xb68/0x2aa0 fs/namei.c:3569 do_filp_open+0x18e/0x250 fs/namei.c:3603 do_sys_open+0x292/0x3e0 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45ca29 RSP: 002b:00007fa0b8c53c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00000000004f7640 RCX: 000000000045ca29 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000007a0 R14: 00000000004ca744 R15: 00007fa0b8c546d4 Showing all locks held in the system: 1 lock held by khungtaskd/1057: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 1 lock held by in:imklog/6004: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xa6/0xc0 fs/file.c:769 4 locks held by syz-executor.2/23898: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&tty->atomic_write_lock){+.+.}, at: [] tty_write_lock+0x1d/0x60 drivers/tty/tty_io.c:885 #2: (&tty->termios_rwsem){++++}, at: [] n_tty_write+0x187/0xe20 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+0x464/0xe20 drivers/tty/n_tty.c:2333 1 lock held by syz-executor.5/23896: #0: (&fb_info->lock){+.+.}, at: [] fb_open+0xb7/0x400 drivers/video/fbdev/core/fbmem.c:1468 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1057 Comm: khungtaskd Not tainted 4.14.182-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+0x1b2/0x283 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x17f lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5e2/0xb80 kernel/hung_task.c:274 kthread+0x30d/0x420 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: 23894 Comm: syz-executor.1 Not tainted 4.14.182-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888058254000 task.stack: ffff888052c10000 RIP: 0010:bitfill_aligned drivers/video/fbdev/core/cfbfillrect.c:44 [inline] RIP: 0010:bitfill_aligned+0x4a/0x190 drivers/video/fbdev/core/cfbfillrect.c:35 RSP: 0018:ffff888052c17328 EFLAGS: 00000246 RAX: 0000000000000050 RBX: ffff8880000a0000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff831c0b3b RDI: 0000000000001400 RBP: 0000000000001400 R08: 0000000000001400 R09: 0000000000000040 R10: ffffed1014bc48a3 R11: ffff8880a5e2451f R12: 0000000000000040 R13: ffffffffffffffff R14: 0000000000000000 R15: 0000000000000000 FS: 00007f3ad95a0700(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c000412634 CR3: 000000009f12c000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: cfb_fillrect+0x3d5/0x720 drivers/video/fbdev/core/cfbfillrect.c:327 vga16fb_fillrect+0x61e/0x1880 drivers/video/fbdev/vga16fb.c:951 bit_clear_margins+0x2a4/0x480 drivers/video/fbdev/core/bitblit.c:232 fbcon_clear_margins+0x274/0x300 drivers/video/fbdev/core/fbcon.c:1320 fbcon_switch+0xc4e/0x1700 drivers/video/fbdev/core/fbcon.c:2302 redraw_screen+0x332/0x760 drivers/tty/vt/vt.c:689 fbcon_modechanged+0x552/0x800 drivers/video/fbdev/core/fbcon.c:2949 fbcon_event_notify+0x11a/0x1750 drivers/video/fbdev/core/fbcon.c:3302 notifier_call_chain+0x107/0x1a0 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+0x79/0x90 kernel/notifier.c:325 fb_set_var+0xaad/0xc70 drivers/video/fbdev/core/fbmem.c:1054 do_fb_ioctl+0x3cc/0x840 drivers/video/fbdev/core/fbmem.c:1127 fb_ioctl+0xda/0x120 drivers/video/fbdev/core/fbmem.c:1242 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45ca29 RSP: 002b:00007f3ad959fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e4ac0 RCX: 000000000045ca29 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002f2 R14: 00000000004c56c8 R15: 00007f3ad95a06d4 Code: 96 3e fe 85 ed 74 5f e8 d5 96 3e fe 41 8d 3c 2e 44 89 f1 31 d2 49 c7 c5 ff ff ff ff 4c 89 e8 48 d3 e0 48 89 04 24 89 f8 41 f7 f4 <89> d1 49 d3 e5 44 39 e7 49 f7 d5 77 41 e8 a4 96 3e fe 4d 85 ed