INFO: task syz.1.1909:13393 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1909 state:D stack:26312 pid:13393 tgid:13391 ppid:5591 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6740 kernel/sched/core.c:7239
__schedule_loop kernel/sched/core.c:7316 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7331
schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75
___down_common kernel/locking/semaphore.c:293 [inline]
__down_common+0x371/0x8b0 kernel/locking/semaphore.c:318
down+0x74/0xa0 kernel/locking/semaphore.c:100
console_lock+0x5b/0xa0 kernel/printk/printk.c:2896
class_console_lock_constructor include/linux/console.h:734 [inline]
con_install+0x99/0x620 drivers/tty/vt/vt.c:3743
tty_driver_install_tty drivers/tty/tty_io.c:1295 [inline]
tty_init_dev.part.0+0x9e/0x470 drivers/tty/tty_io.c:1407
tty_init_dev include/linux/err.h:78 [inline]
tty_open_by_driver drivers/tty/tty_io.c:2073 [inline]
tty_open+0xa63/0xfa0 drivers/tty/tty_io.c:2120
chrdev_open+0x234/0x6a0 fs/char_dev.c:411
do_dentry_open+0x6ab/0x14d0 fs/open.c:996
vfs_open+0x82/0x3f0 fs/open.c:1101
do_open fs/namei.c:4837 [inline]
path_openat+0x19fa/0x2440 fs/namei.c:5000
do_file_open+0x20e/0x430 fs/namei.c:5029
do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1434
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc9e975e90e
RSP: 002b:00007fc9ea688b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fc9ea6896c0 RCX: 00007fc9e975e90e
RDX: 0000000000000002 RSI: 00007fc9ea688c00 RDI: ffffffffffffff9c
RBP: 00007fc9e9835024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc9e9a26038 R14: 00007fc9e9a25fa0 R15: 00007ffe3931bb18
INFO: task syz.6.1912:13400 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1912 state:D stack:27592 pid:13400 tgid:13398 ppid:12953 task_flags:0x400140 flags:0x00080006
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6740 kernel/sched/core.c:7239
__schedule_loop kernel/sched/core.c:7316 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7331
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7388
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xcbf/0x1bc0 kernel/locking/mutex.c:821
tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
chrdev_open+0x234/0x6a0 fs/char_dev.c:411
do_dentry_open+0x6ab/0x14d0 fs/open.c:996
vfs_open+0x82/0x3f0 fs/open.c:1101
do_open fs/namei.c:4837 [inline]
path_openat+0x19fa/0x2440 fs/namei.c:5000
do_file_open+0x20e/0x430 fs/namei.c:5029
do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1434
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f20f779e0d9
RSP: 002b:00007f20f85fb028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f20f7a25fa0 RCX: 00007f20f779e0d9
RDX: 0000000000002982 RSI: 0000200000000180 RDI: ffffffffffffff9c
RBP: 00007f20f7835024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f20f7a26038 R14: 00007f20f7a25fa0 R15: 00007fffe75acc18
Showing all locks held in the system:
locks held by kworker/u8:0/12: 2, on CPU#0:
#0: ffff88801fb4e140 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc90000117d08 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
locks held by khungtaskd/30: 1, last CPU#0:
#0: ffffffff8ede9440 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8ede9440 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8ede9440 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6793
locks held by kworker/u8:3/48: 2, on CPU#0:
#0: ffff88801fb4e140 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc90000b97d08 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
locks held by kworker/u8:7/321: 2, on CPU#0:
#0: ffff88801fb4e140 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc9000337fd08 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
locks held by getty/5351: 2, on CPU#0:
#0: ffff8880375160a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
locks held by kworker/u8:12/6216: 2, on CPU#0:
#0: ffff88801fb4e140 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc9000d8d7d08 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
locks held by kworker/u8:4/11220: 2, on CPU#0:
#0: ffff88801fb4e140 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc90002f9fd08 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
locks held by kworker/0:4/12018: 3, last CPU#0:
#0: ffff88801c04b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc90005597d08 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff888058205250 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1b8/0x6330 drivers/net/netdevsim/fib.c:1490
locks held by syz.0.1779/12835: 6, last CPU#0:
#0: ffff8880340560a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffff888034056128 (&tty->atomic_write_lock){+.+.}-{4:4}, at: tty_write_lock drivers/tty/tty_io.c:939 [inline]
#1: ffff888034056128 (&tty->atomic_write_lock){+.+.}-{4:4}, at: iterate_tty_write drivers/tty/tty_io.c:958 [inline]
#1: ffff888034056128 (&tty->atomic_write_lock){+.+.}-{4:4}, at: file_tty_write.isra.0+0x24b/0x890 drivers/tty/tty_io.c:1081
#2: ffff8880340562c8 (&tty->termios_rwsem){++++}-{4:4}, at: class_rwsem_read_constructor include/linux/rwsem.h:259 [inline]
#2: ffff8880340562c8 (&tty->termios_rwsem){++++}-{4:4}, at: n_tty_write+0x1b8/0x1160 drivers/tty/n_tty.c:2349
#3: ffffc90005719370 (&ldata->output_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#3: ffffc90005719370 (&ldata->output_lock){+.+.}-{4:4}, at: process_output_block drivers/tty/n_tty.c:513 [inline]
#3: ffffc90005719370 (&ldata->output_lock){+.+.}-{4:4}, at: n_tty_write+0x54c/0x1160 drivers/tty/n_tty.c:2366
#4: ffffffff8edd5800 (console_lock){+.+.}-{0:0}, at: class_console_lock_constructor include/linux/console.h:734 [inline]
#4: ffffffff8edd5800 (console_lock){+.+.}-{0:0}, at: do_con_write+0x15b/0x4980 drivers/tty/vt/vt.c:3290
#5: ffffffff8edd5878 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:305 [inline]
#5: ffffffff8edd5878 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:428 [inline]
#5: ffffffff8edd5878 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:291 [inline]
#5: ffffffff8edd5878 (console_srcu){....}-{0:0}, at: console_flush_one_record+0xfd/0xe50 kernel/printk/printk.c:3246
locks held by syz.1.1909/13393: 2, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
#1: ffff88807ef7c1b0 (&tty->legacy_mutex){+.+.}-{4:4}, at: tty_init_dev.part.0+0x39/0x470 drivers/tty/tty_io.c:1406
locks held by syz.6.1912/13400: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.4.1926/13478: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.3.1940/13541: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.5.1941/13543: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.7.1949/13654: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.9.1963/13762: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by kworker/u8:14/14000: 3, on CPU#0:
#0: ffff888032ec7140 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc900052c7d08 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffffffff90c9c9c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff90c9c9c0 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11f/0x1360 net/ipv6/addrconf.c:4229
locks held by syz.1.1983/14022: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.2.1988/14048: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.8.2017/14304: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.5.2041/14463: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: ptmx_open drivers/tty/pty.c:800 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: ptmx_open+0x11a/0x360 drivers/tty/pty.c:767
locks held by syz.4.2060/14574: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.6.2073/14653: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.6.2073/14654: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.0.2074/14668: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.3.2075/14679: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz.7.2084/14720: 1, on CPU#0:
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8fb89920 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x539/0xfa0 drivers/tty/tty_io.c:2120
locks held by syz-executor/14783: 1, last CPU#0:
#0: ffffffff90c9c9c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff90c9c9c0 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x49c/0x1bb0 net/ipv6/addrconf.c:5062
locks held by syz-executor/14785: 1, on CPU#0:
#0: ffffffff90c9c9c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff90c9c9c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff90c9c9c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8bb/0x2380 net/core/rtnetlink.c:4158
locks held by syz-executor/14865: 2, on CPU#0:
#0: ffffffff91425d48 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline]
#0: ffffffff91425d48 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline]
#0: ffffffff91425d48 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x113/0x2c0 net/core/rtnetlink.c:574
#1: ffffffff90c9c9c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff90c9c9c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff90c9c9c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8bb/0x2380 net/core/rtnetlink.c:4158
locks held by kworker/u8:18/14880: 2, last CPU#0:
#0: ffff8880267a6940 ((wq_completion)nvme-wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc9000710fd08 ((work_completion)(&(&ctrl->connect_work)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x21f/0x2a0 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245