INFO: task syz-executor.4:5673 blocked for more than 143 seconds. Not tainted 5.9.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:26600 pid: 5673 ppid: 346 flags:0x80004006 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x889/0x1f70 kernel/sched/core.c:4527 schedule+0xcd/0x2b0 kernel/sched/core.c:4602 wdm_flush+0x2e9/0x3c0 drivers/usb/class/cdc-wdm.c:590 filp_close+0xb4/0x170 fs/open.c:1276 close_files fs/file.c:401 [inline] put_files_struct fs/file.c:429 [inline] put_files_struct+0x1d0/0x350 fs/file.c:426 exit_files+0x7e/0xa0 fs/file.c:458 do_exit+0xb75/0x2890 kernel/exit.c:801 do_group_exit+0x125/0x310 kernel/exit.c:903 get_signal+0x42d/0x1f10 kernel/signal.c:2757 arch_do_signal+0x88/0x1a00 arch/x86/kernel/signal.c:811 exit_to_user_mode_loop kernel/entry/common.c:135 [inline] exit_to_user_mode_prepare+0xf9/0x150 kernel/entry/common.c:166 syscall_exit_to_user_mode+0x36/0x260 kernel/entry/common.c:241 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007f5c5ca37c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: fffffffffffffff2 RBX: 0000000000038f00 RCX: 000000000045d5b9 RDX: 00000000ffffffa3 RSI: 0000000020000040 RDI: 0000000000000009 RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007ffcebe6cfef R14: 00007f5c5ca389c0 R15: 000000000118cf4c INFO: task syz-executor.5:5745 blocked for more than 143 seconds. Not tainted 5.9.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:28960 pid: 5745 ppid: 341 flags:0x80004006 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x889/0x1f70 kernel/sched/core.c:4527 schedule+0xcd/0x2b0 kernel/sched/core.c:4602 wdm_flush+0x2e9/0x3c0 drivers/usb/class/cdc-wdm.c:590 filp_close+0xb4/0x170 fs/open.c:1276 close_files fs/file.c:401 [inline] put_files_struct fs/file.c:429 [inline] put_files_struct+0x1d0/0x350 fs/file.c:426 exit_files+0x7e/0xa0 fs/file.c:458 do_exit+0xb75/0x2890 kernel/exit.c:801 do_group_exit+0x125/0x310 kernel/exit.c:903 get_signal+0x42d/0x1f10 kernel/signal.c:2757 arch_do_signal+0x88/0x1a00 arch/x86/kernel/signal.c:811 exit_to_user_mode_loop kernel/entry/common.c:135 [inline] exit_to_user_mode_prepare+0xf9/0x150 kernel/entry/common.c:166 syscall_exit_to_user_mode+0x36/0x260 kernel/entry/common.c:241 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007fdc4905ecf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000118cfe8 RCX: 000000000045d5b9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000118cfe8 RBP: 000000000118cfe0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cfec R13: 00007fff2427ff7f R14: 00007fdc4905f9c0 R15: 000000000118cfec Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: ffffffff87313620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5825 4 locks held by systemd-journal/108: 1 lock held by in:imklog/241: 2 locks held by agetty/247: #0: ffff8881d6f8a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900009ea2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.9.0-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:77 [inline] dump_stack+0xf6/0x16e lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x74/0xb6 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1da/0x1f4 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd6a/0xfd0 kernel/hung_task.c:295 kthread+0x392/0x470 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 0 to CPUs 1: cdc_wdm 5-1:118.0: wdm_int_callback - 0 bytes cdc_wdm 5-1:118.0: nonzero urb status received: -71 NMI backtrace for cpu 1 CPU: 1 PID: 108 Comm: systemd-journal Not tainted 5.9.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:io_serial_out+0x68/0x80 drivers/tty/serial/8250/8250_port.c:454 Code: f1 00 00 00 48 8d 7d 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 15 03 5d 40 44 89 e0 89 da ee <5b> 5d 41 5c c3 e8 de 3c 40 ff eb c7 e8 07 3d 40 ff eb e4 0f 1f 44 RSP: 0018:ffff8881db3094e8 EFLAGS: 00000006 RAX: 0000000000000000 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: ffffffff8229a391 RDI: ffffffff8a2bcaa0 RBP: ffffffff8a2bca60 R08: 0000000000000001 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000003254 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8a2bcab8 R15: ffffffff8a2bcab0 FS: 00007f40583548c0(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f40548d9000 CR3: 00000001d1c9a000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_port_out include/linux/serial_core.h:267 [inline] serial8250_console_write+0x584/0xa90 drivers/tty/serial/8250/8250_port.c:3296 call_console_drivers kernel/printk/printk.c:1824 [inline] console_unlock+0x87a/0xcd0 kernel/printk/printk.c:2501 vprintk_emit+0x1b2/0x460 kernel/printk/printk.c:2029 dev_vprintk_emit+0x3eb/0x436 drivers/base/core.c:4133 dev_printk_emit+0xba/0xf1 drivers/base/core.c:4144 __dev_printk+0xcf/0xf5 drivers/base/core.c:4156 _dev_err+0xd7/0x109 drivers/base/core.c:4199 wdm_int_callback.cold+0x82/0x2a6 drivers/usb/class/cdc-wdm.c:252 __usb_hcd_giveback_urb+0x32d/0x560 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x367/0x410 drivers/usb/core/hcd.c:1716 dummy_timer+0x11f2/0x3240 drivers/usb/gadget/udc/dummy_hcd.c:1967 call_timer_fn+0x1ac/0x6e0 kernel/time/timer.c:1413 expire_timers kernel/time/timer.c:1458 [inline] __run_timers.part.0+0x67c/0xa60 kernel/time/timer.c:1755 __run_timers kernel/time/timer.c:1736 [inline] run_timer_softirq+0x80/0x120 kernel/time/timer.c:1768 __do_softirq+0x1af/0x91c kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x73/0x90 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x107/0x1a0 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x43/0x90 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:lock_acquire+0x1de/0x950 kernel/locking/lockdep.c:4977 Code: 03 38 d0 7c 08 84 d2 0f 85 4b 06 00 00 8b 83 9c 08 00 00 83 e8 01 66 85 c0 89 83 9c 08 00 00 0f 85 08 05 00 00 ff 74 24 08 9d <48> b8 00 00 00 00 00 fc ff df 48 03 44 24 10 48 c7 00 00 00 00 00 RSP: 0018:ffff8881d2207728 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8881d26ee500 RCX: ffffffff81267b6a RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8881d26eed9c RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff895c65ef R10: fffffbfff12b8cbd R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff873f19a8 R14: 0000000000000000 R15: 0000000000000001 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10a0 kernel/locking/mutex.c:1103 kernfs_dop_revalidate+0x98/0x3a0 fs/kernfs/dir.c:563 d_revalidate fs/namei.c:768 [inline] d_revalidate fs/namei.c:765 [inline] lookup_fast+0x38e/0x6c0 fs/namei.c:1505 walk_component+0xc6/0x6a0 fs/namei.c:1856 lookup_last fs/namei.c:2309 [inline] path_lookupat+0x1ba/0x830 fs/namei.c:2333 filename_lookup+0x19f/0x560 fs/namei.c:2366 user_path_at include/linux/namei.h:59 [inline] vfs_statx+0x14e/0x390 fs/stat.c:202 vfs_lstat include/linux/fs.h:3175 [inline] __do_sys_newlstat+0x91/0x110 fs/stat.c:374 do_syscall_64+0x2d/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f4057610335 Code: 69 db 2b 00 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 83 ff 01 48 89 f0 77 30 48 89 c7 48 89 d6 b8 06 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 03 f3 c3 90 48 8b 15 31 db 2b 00 f7 d8 64 89 RSP: 002b:00007ffc81f8f418 EFLAGS: 00000246 ORIG_RAX: 0000000000000006 RAX: ffffffffffffffda RBX: 0000557cde8b5970 RCX: 00007f4057610335 RDX: 00007ffc81f8f450 RSI: 00007ffc81f8f450 RDI: 0000557cde8b4970 RBP: 00007ffc81f8f510 R08: 0000000000000003 R09: 0000000000001010 R10: 0000000000000090 R11: 0000000000000246 R12: 0000557cde8b4970 R13: 0000557cde8b4996 R14: 0000557cde8b445b R15: 0000557cde8b445f