INFO: task syz-executor.0:4604 blocked for more than 143 seconds. Not tainted 5.3.0-rc2+ #25 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28520 4604 1743 0x80004006 Call Trace: schedule+0x9a/0x250 kernel/sched/core.c:3944 wdm_flush+0x20c/0x370 drivers/usb/class/cdc-wdm.c:590 filp_close+0xb4/0x160 fs/open.c:1166 close_files fs/file.c:388 [inline] put_files_struct fs/file.c:416 [inline] put_files_struct+0x1d8/0x2e0 fs/file.c:413 exit_files+0x7e/0xa0 fs/file.c:445 do_exit+0x8bc/0x2c50 kernel/exit.c:873 do_group_exit+0x125/0x340 kernel/exit.c:982 get_signal+0x466/0x23d0 kernel/signal.c:2728 do_signal+0x88/0x14e0 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x1a2/0x200 arch/x86/entry/common.c:159 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x45f/0x580 arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457cf1 Code: 20 80 00 00 8b 8c 24 28 80 00 00 8b 9c 24 2c 80 00 00 48 89 e6 48 01 df 48 01 de 48 29 d9 e8 56 f8 ff ff 48 8b ac 24 00 80 00 <00> 48 81 c4 08 80 00 00 c3 e8 41 f6 ff ff e9 4c ff ff ff 48 8d bc RSP: 002b:00007fffbdfc3a40 EFLAGS: 00000293 ORIG_RAX: 0000000000000023 RAX: fffffffffffffdfc RBX: 000000000002cb7b RCX: 0000000000457cf1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007fffbdfc3a50 RBP: 0000000000000001 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007fffbdfc3b40 R11: 0000000000000293 R12: 000000000075bf20 R13: 000000000075c9a0 R14: 00000000007602c0 R15: ffffffffffffffff INFO: task syz-executor.1:4609 blocked for more than 143 seconds. Not tainted 5.3.0-rc2+ #25 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28520 4609 1756 0x00000004 Call Trace: schedule+0x9a/0x250 kernel/sched/core.c:3944 wdm_flush+0x20c/0x370 drivers/usb/class/cdc-wdm.c:590 filp_close+0xb4/0x160 fs/open.c:1166 __close_fd+0x133/0x200 fs/file.c:636 __do_sys_close fs/open.c:1185 [inline] __se_sys_close fs/open.c:1183 [inline] __x64_sys_close+0x69/0x100 fs/open.c:1183 do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413511 Code: c8 48 c1 e8 03 48 83 c0 03 48 c1 e8 02 48 8b 8c 24 90 00 00 00 48 c1 e9 05 48 8b 54 24 68 48 89 d3 48 29 c2 48 29 cb 48 89 d8 <48> ff c0 48 89 04 24 48 29 da 48 89 54 24 08 e8 6b 6c 04 00 48 8b RSP: 002b:00007fff977f65a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000413511 RDX: 0000001b30920000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00000000c109b3a0 R09: 00000000c109b3a4 R10: 00007fff977f6680 R11: 0000000000000293 R12: 000000000075bf20 R13: 000000000002c300 R14: 0000000000760268 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: 000000006e9fca03 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:5254 1 lock held by rsyslogd/1602: #0: 0000000003be5e98 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:801 2 locks held by getty/1692: #0: 0000000015962e96 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000001a908db2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1693: #0: 000000003edbed2b (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 0000000011bb37fb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1694: #0: 00000000b9a5fbf3 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 0000000093efe323 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1695: #0: 000000002893c980 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000008ad5efd5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1696: #0: 00000000da759aac (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000bfbb7fb3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1697: #0: 00000000f7406d8b (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000904bea1c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1698: #0: 0000000048c6ebc0 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000c9adbc98 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 23 Comm: khungtaskd Not tainted 5.3.0-rc2+ #25 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+0xca/0x13e lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x55/0x96 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1c7 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0x9a4/0xe50 kernel/hung_task.c:289 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline] NMI backtrace for cpu 0 skipped: idling at default_idle+0x28/0x2e0 arch/x86/kernel/process.c:580