INFO: task syz.0.2128:14606 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.0.2128 state:D stack:28728 pid:14606 tgid:14605 ppid:13652 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5520 [inline]
__schedule+0x1259/0x6920 kernel/sched/core.c:7270
__schedule_loop kernel/sched/core.c:7347 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7362
cgroup_lock_and_drain_offline+0x383/0x800 kernel/cgroup/cgroup.c:3350
cgroup1_get_tree+0xc2/0x1620 kernel/cgroup/cgroup-v1.c:1265
vfs_get_tree+0x92/0x320 fs/super.c:1947
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
do_mount fs/namespace.c:4181 [inline]
__do_sys_mount fs/namespace.c:4397 [inline]
__se_sys_mount fs/namespace.c:4374 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4374
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: 0033:0x7fd81159e159
RSP: 002b:00007fd8124c6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fd811825fa0 RCX: 00007fd81159e159
RDX: 0000200000000080 RSI: 0000200000000040 RDI: 0000000000000000
RBP: 00007fd811635024 R08: 0000200000000140 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd811826038 R14: 00007fd811825fa0 R15: 00007ffef7302568
Showing all locks held in the system:
locks held by kworker/0:0/9: 2, last CPU#0:
#0: ffff88801c0bed40 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc900000e7d08 ((work_completion)(&(&ssp->srcu_sup->work)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by khungtaskd/32: 1, last CPU#1:
#0: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6837
locks held by kworker/u9:0/52: 2, on CPU#0:
#0: ffff888028efb140 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90000bc7d08 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by syz-executor/5596: 4, last CPU#1:
#0: ffffffff8ef3cc30 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1542 [inline]
#0: ffffffff8ef3cc30 (dup_mmap_sem){++++}-{0:0}, at: copy_mm kernel/fork.c:1595 [inline]
#0: ffffffff8ef3cc30 (dup_mmap_sem){++++}-{0:0}, at: copy_process+0x4806/0x8370 kernel/fork.c:2307
#1: ffff88807ee6f678 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#1: ffff88807ee6f678 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x127/0x2370 mm/mmap.c:1716
#2: ffff88807d98d038 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline]
#2: ffff88807d98d038 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x1c9/0x2370 mm/mmap.c:1723
#3: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#3: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#3: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x310 mm/pgtable-generic.c:290
locks held by kworker/u9:2/5601: 2, on CPU#0:
#0: ffff888028efb140 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90004237d08 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by kworker/u9:3/5602: 2, on CPU#0:
#0: ffff888028f98140 ((wq_completion)nbd1-recv){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90004247d08 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by kworker/u9:4/5609: 2, on CPU#0:
#0: ffff888028f98140 ((wq_completion)nbd1-recv){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90004267d08 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by kworker/u9:6/5611: 2, on CPU#1:
#0: ffff888028efb140 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90004fffd08 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by kworker/u8:26/7111: 2, last CPU#0:
#0: ffff888034dc6940 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90003517d08 ((work_completion)(&(&bat_priv->tt.work)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by udevd/9612: 1, last CPU#1:
#0: ffff88801da80460 (sb_writers){.+.+}-{0:0}, at: vfs_utimes+0x6b4/0x880 fs/utimes.c:37
locks held by kworker/u9:1/11290: 2, on CPU#0:
#0: ffff888028f98140 ((wq_completion)nbd1-recv){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc9000df37d08 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by syz-executor/12196: 4, last CPU#1:
#0: ffffffff8ef3cc30 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1542 [inline]
#0: ffffffff8ef3cc30 (dup_mmap_sem){++++}-{0:0}, at: copy_mm kernel/fork.c:1595 [inline]
#0: ffffffff8ef3cc30 (dup_mmap_sem){++++}-{0:0}, at: copy_process+0x4806/0x8370 kernel/fork.c:2307
#1: ffff88801ef05038 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#1: ffff88801ef05038 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x127/0x2370 mm/mmap.c:1716
#2: ffff88807d98f678 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline]
#2: ffff88807d98f678 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x1c9/0x2370 mm/mmap.c:1723
#3: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#3: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#3: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x310 mm/pgtable-generic.c:290
locks held by syz.1.1765/13005: 1, last CPU#1:
#0: ffff88805b5b5690 (&ima_iint_mutex_key[depth]#3){+.+.}-{4:4}, at: process_measurement+0x5ab/0x2350 security/integrity/ima/ima_main.c:319
locks held by kworker/u8:10/14204: 2, on CPU#0:
#0: ffff88801c094140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90004e7fd08 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by syz-executor/14798: 1, last CPU#1:
#0: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#0: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
locks held by getty/15927: 2, on CPU#1:
#0: ffff88802bdfb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc90003eb52e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
locks held by syz.2.2729/16431: 1, on CPU#1:
#0: ffff88807e9083b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#0: ffff88807e9083b8 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1f5/0x470 mm/util.c:579
locks held by syz.2.2729/16432: 2, last CPU#1:
#0: ffff88807e9083b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline]
#0: ffff88807e9083b8 (&mm->mmap_lock){++++}-{4:4}, at: __mm_populate+0x229/0x3a0 mm/gup.c:1942
#1: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#1: ffffffff8edec060 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
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:123
nmi_trigger_cpumask_backtrace+0x21f/0x2a0 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [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
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 16 Comm: pr/ttyS0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:410
Code: e5 5b fc 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c e9 0d 1c 23 06 e8 78 08 cf fc eb a2 e8 01 09
RSP: 0018:ffffc90000157958 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff85b01a20 RDI: ffffffff9bc65ca0
RBP: ffffffff9bc65c60 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 205d323354202020 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff378cbe9 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888123c5f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe28bdf14b8 CR3: 000000007d2c8000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x13a/0x210 drivers/tty/serial/8250/8250_port.c:2013
serial8250_fifo_wait_for_lsr_thre+0x5f/0xd0 drivers/tty/serial/8250/8250_port.c:3270
__serial8250_console_fifo_write+0xa5/0x290 drivers/tty/serial/8250/8250_port.c:3345
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline]
__serial8250_console_write drivers/tty/serial/8250/8250_port.c:3429 [inline]
serial8250_console_write+0xf46/0x1330 drivers/tty/serial/8250/8250_port.c:3493
nbcon_emit_next_record+0x8f7/0xa70 kernel/printk/nbcon.c:1070
nbcon_emit_one+0x1a8/0x2b0 kernel/printk/nbcon.c:1157
nbcon_kthread_func+0x613/0x7d0 kernel/printk/nbcon.c:1271
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