INFO: task kworker/u4:2:16778 blocked for more than 143 seconds. Not tainted 5.15.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:2 state:D stack:24176 pid:16778 ppid: 2 flags:0x00004000 Workqueue: events_unbound flush_to_ldisc Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x947/0x22b0 kernel/sched/core.c:6287 schedule+0xcf/0x270 kernel/sched/core.c:6366 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857 __down_common+0x2e0/0x420 kernel/locking/semaphore.c:224 down+0x72/0xa0 kernel/locking/semaphore.c:62 console_lock+0x2a/0x80 kernel/printk/printk.c:2523 do_con_write+0x10f/0x1e40 drivers/tty/vt/vt.c:2908 con_put_char+0x70/0xa0 drivers/tty/vt/vt.c:3303 tty_put_char+0xb7/0x150 drivers/tty/tty_io.c:3173 __process_echoes+0x583/0x9f0 drivers/tty/n_tty.c:726 flush_echoes drivers/tty/n_tty.c:826 [inline] __receive_buf drivers/tty/n_tty.c:1579 [inline] n_tty_receive_buf_common+0x1699/0x4780 drivers/tty/n_tty.c:1674 tty_ldisc_receive_buf+0xa3/0x190 drivers/tty/tty_buffer.c:471 tty_port_default_receive_buf+0x6e/0xa0 drivers/tty/tty_port.c:39 receive_buf drivers/tty/tty_buffer.c:491 [inline] flush_to_ldisc+0x20d/0x380 drivers/tty/tty_buffer.c:543 process_one_work+0x9bf/0x1620 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3c2/0x4a0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: task syz-executor.5:13843 blocked for more than 143 seconds. Not tainted 5.15.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:28656 pid:13843 ppid: 3709 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x947/0x22b0 kernel/sched/core.c:6287 schedule+0xcf/0x270 kernel/sched/core.c:6366 synchronize_rcu_expedited+0x499/0x640 kernel/rcu/tree_exp.h:853 synchronize_rcu+0x154/0x1b0 kernel/rcu/tree.c:3746 evdev_detach_client drivers/input/evdev.c:386 [inline] evdev_release+0x23f/0x410 drivers/input/evdev.c:449 __fput+0x288/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xbae/0x2890 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2170 kernel/signal.c:2868 arch_do_signal_or_restart+0x2a9/0x1c10 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x15d/0x220 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f45196944c7 RSP: 002b:00007f45173e90b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffffc RBX: 00007f45173ea130 RCX: 00007f45196944c7 RDX: 00007f45173ea130 RSI: 0000000080085502 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000ffff R09: 000000000000000b R10: 00007f45173e9180 R11: 0000000000000246 R12: 0000000800000000 R13: 0000000000000000 R14: 0000000020000180 R15: 00007f45196fa0b6 Showing all locks held in the system: 6 locks held by kworker/1:0/17: #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x8a3/0x1620 kernel/workqueue.c:2268 #1: ffffc9000012fdb0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x1620 kernel/workqueue.c:2272 #2: ffff88810cde5220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #2: ffff88810cde5220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4330 drivers/usb/core/hub.c:5662 #3: ffff88811f26e220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #3: ffff88811f26e220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944 #4: ffff8881143ae1a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #4: ffff8881143ae1a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944 #5: ffff8881128d0ce0 (&dev->phy_mutex){+.+.}-{3:3}, at: asix_mdio_read+0x86/0x220 drivers/net/usb/asix_common.c:495 1 lock held by khungtaskd/24: #0: ffffffff87681ea0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/2808: #0: ffff88811706fc70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 1 lock held by syz-executor.5/3709: #0: ffffffff876889e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #0: ffffffff876889e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2fb/0x640 kernel/rcu/tree_exp.h:837 6 locks held by kworker/1:6/5797: #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff8881035fcd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x8a3/0x1620 kernel/workqueue.c:2268 #1: ffffc900030c7db0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x1620 kernel/workqueue.c:2272 #2: ffff88810cc5d220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #2: ffff88810cc5d220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4330 drivers/usb/core/hub.c:5662 #3: ffff88811d384220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #3: ffff88811d384220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944 #4: ffff888118def1a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #4: ffff888118def1a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944 #5: ffff8881065b4ce0 (&dev->phy_mutex){+.+.}-{3:3}, at: asix_mdio_read+0x86/0x220 drivers/net/usb/asix_common.c:495 3 locks held by kworker/1:2/21761: 2 locks held by agetty/8480: #0: ffff88811d43f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc9000209b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 6 locks held by kworker/u4:2/16778: #0: ffff888100069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888100069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888100069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888100069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888100069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888100069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x8a3/0x1620 kernel/workqueue.c:2268 #1: ffffc90012ba7db0 ((work_completion)(&buf->work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x1620 kernel/workqueue.c:2272 #2: ffff88811608d0b8 (&buf->lock){+.+.}-{3:3}, at: flush_to_ldisc+0x3e/0x380 drivers/tty/tty_buffer.c:515 #3: ffff8881169e9098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1d/0x80 drivers/tty/tty_ldisc.c:273 #4: ffff8881169e92e8 (&tty->termios_rwsem){++++}-{3:3}, at: n_tty_receive_buf_common+0x84/0x4780 drivers/tty/n_tty.c:1637 #5: ffffc9000182b378 (&ldata->output_lock){+.+.}-{3:3}, at: flush_echoes drivers/tty/n_tty.c:824 [inline] #5: ffffc9000182b378 (&ldata->output_lock){+.+.}-{3:3}, at: __receive_buf drivers/tty/n_tty.c:1579 [inline] #5: ffffc9000182b378 (&ldata->output_lock){+.+.}-{3:3}, at: n_tty_receive_buf_common+0x1663/0x4780 drivers/tty/n_tty.c:1674 2 locks held by agetty/353: #0: ffff8881169e9098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc9000182b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 1 lock held by syz-executor.5/13843: #0: ffffffff876889e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #0: ffffffff876889e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x522/0x640 kernel/rcu/tree_exp.h:837 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 24 Comm: khungtaskd Not tainted 5.15.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x49/0x148 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1d5/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc0f/0xf20 kernel/hung_task.c:295 kthread+0x3c2/0x4a0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1154 Comm: systemd-journal Not tainted 5.15.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:number+0x16a/0xae0 lib/vsprintf.c:465 Code: 30 89 d8 83 e0 20 88 44 24 37 89 d8 83 e0 02 89 c5 89 c6 88 44 24 34 e8 74 79 31 ff 40 84 ed 0f 85 c7 06 00 00 e8 36 72 31 ff <83> e3 12 88 5c 24 36 e8 2a 72 31 ff 0f b6 5c 24 04 31 ff 83 e3 01 RSP: 0018:ffffc90000267730 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000020 RCX: 0000000000000000 RDX: ffff88811285d1c0 RSI: ffffffff8210467a RDI: 0000000000000003 RBP: 0000000000000000 R08: 000000000000002f R09: 0000000000000000 R10: ffffffff8210466c R11: 0000000000000000 R12: ffff888114c6e24a R13: ffffffff8684e22d R14: ffff888114c6ea1c R15: ffff888114c6e24a FS: 00007f34db4248c0(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f34d676e008 CR3: 000000010d239000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vsnprintf+0xf09/0x14f0 lib/vsprintf.c:2863 add_uevent_var+0x15d/0x380 lib/kobject_uevent.c:665 usb_uevent+0x1b7/0x490 drivers/usb/core/driver.c:926 dev_uevent+0x202/0x780 drivers/base/core.c:2294 uevent_show+0x1bb/0x390 drivers/base/core.c:2358 dev_attr_show+0x4b/0x90 drivers/base/core.c:2060 sysfs_kf_seq_show+0x1f8/0x400 fs/sysfs/file.c:61 seq_read_iter+0x4f6/0x1240 fs/seq_file.c:230 kernfs_fop_read_iter+0x44f/0x5f0 fs/kernfs/file.c:241 call_read_iter include/linux/fs.h:2157 [inline] new_sync_read+0x400/0x6b0 fs/read_write.c:404 vfs_read+0x35c/0x600 fs/read_write.c:485 ksys_read+0x12d/0x250 fs/read_write.c:623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f34da6df92d Code: 2d 2c 00 00 75 10 b8 00 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 de 9b 01 00 48 89 04 24 b8 00 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 27 9c 01 00 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffed5155f80 EFLAGS: 00000293 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000055be22c64c70 RCX: 00007f34da6df92d RDX: 0000000000001000 RSI: 000055be22c66800 RDI: 0000000000000010 RBP: 00007f34da99a440 R08: 0000000000000003 R09: 0000000000001010 R10: 000055be22c64c70 R11: 0000000000000293 R12: 0000000000001000 R13: 0000000000000d68 R14: 000055be22c66800 R15: 00007f34da999900 ---------------- Code disassembly (best guess): 0: 30 89 d8 83 e0 20 xor %cl,0x20e083d8(%rcx) 6: 88 44 24 37 mov %al,0x37(%rsp) a: 89 d8 mov %ebx,%eax c: 83 e0 02 and $0x2,%eax f: 89 c5 mov %eax,%ebp 11: 89 c6 mov %eax,%esi 13: 88 44 24 34 mov %al,0x34(%rsp) 17: e8 74 79 31 ff callq 0xff317990 1c: 40 84 ed test %bpl,%bpl 1f: 0f 85 c7 06 00 00 jne 0x6ec 25: e8 36 72 31 ff callq 0xff317260 * 2a: 83 e3 12 and $0x12,%ebx <-- trapping instruction 2d: 88 5c 24 36 mov %bl,0x36(%rsp) 31: e8 2a 72 31 ff callq 0xff317260 36: 0f b6 5c 24 04 movzbl 0x4(%rsp),%ebx 3b: 31 ff xor %edi,%edi 3d: 83 e3 01 and $0x1,%ebx