INFO: task syz-executor.0:13374 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.0 state:D stack:29264 pid:13374 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:00007f396ec8ccf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000118d128 RCX: 000000000045d5b9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000118d128 RBP: 000000000118d120 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118d12c R13: 00007ffc6625326f R14: 00007f396ec8d9c0 R15: 000000000118d12c INFO: task syz-executor.1:13343 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.1 state:D stack:28816 pid:13343 ppid: 349 flags:0x00000004 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_fd+0x2f/0x50 fs/file.c:671 __do_sys_close fs/open.c:1295 [inline] __se_sys_close fs/open.c:1293 [inline] __x64_sys_close+0x69/0x100 fs/open.c:1293 do_syscall_64+0x2d/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x416f01 Code: Bad RIP value. RSP: 002b:00007ffd2860f130 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000416f01 RDX: 0000000000000000 RSI: 0000000000000081 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000001190b40 R09: 0000000000000000 R10: 00007ffd2860f210 R11: 0000000000000293 R12: 0000000001190b48 R13: 0000000000000001 R14: ffffffffffffffff R15: 000000000118cfec INFO: task syz-executor.3:13348 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.3 state:D stack:28816 pid:13348 ppid: 347 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: 0033:0x45ba81 Code: Bad RIP value. RSP: 002b:00007ffdc597fed0 EFLAGS: 00000293 ORIG_RAX: 0000000000000023 RAX: fffffffffffffdfc RBX: 000000000007f78e RCX: 000000000045ba81 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007ffdc597fee0 RBP: 0000000000000001 R08: 00000000a695e6fb R09: 00000000a695e6ff R10: 00007ffdc597ffe0 R11: 0000000000000293 R12: 000000000118cf40 R13: 000000000118d940 R14: ffffffffffffffff R15: 000000000118cfec INFO: task syz-executor.4:13457 blocked for more than 144 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:29264 pid:13457 ppid: 348 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:00007ff7d4a70cf8 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: 00007ffd274da6af R14: 00007ff7d4a719c0 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 3 locks held by in:imklog/220: #0: ffff8881c8bd2ff0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 #1: ffffffff873a3a40 (fs_reclaim){+.+.}-{0:0}, at: syslog_print kernel/printk/printk.c:1400 [inline] #1: ffffffff873a3a40 (fs_reclaim){+.+.}-{0:0}, at: do_syslog.part.0+0x4a0/0x1340 kernel/printk/printk.c:1565 #2: ffffffff87313620 (rcu_read_lock){....}-{1:2}, at: trace_sched_stat_runtime include/trace/events/sched.h:435 [inline] #2: ffffffff87313620 (rcu_read_lock){....}-{1:2}, at: update_curr+0x28a/0x820 kernel/sched/fair.c:869 2 locks held by agetty/6941: #0: ffff8881cef54098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000fef32e8 (&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: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x72/0x90 drivers/acpi/processor_idle.c:111