INFO: task syz.0.1192:9423 blocked for more than 143 seconds.
Tainted: G S L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1192 state:D stack:28128 pid:9423 tgid:9421 ppid:5609 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7474
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
bdev_open+0xde/0xd70 block/bdev.c:990
bdev_file_open_by_dev+0x1be/0x240 block/bdev.c:1104
fs_bdev_file_open_by_dev fs/super.c:1710 [inline]
setup_bdev_super+0x5a/0x680 fs/super.c:1802
get_tree_bdev_flags+0x388/0x4f0 fs/super.c:1881
vfs_get_tree+0x92/0x2a0 fs/super.c:1943
fc_mount fs/namespace.c:1282 [inline]
do_new_mount_fc fs/namespace.c:3910 [inline]
do_new_mount+0x325/0xb00 fs/namespace.c:3986
do_mount fs/namespace.c:4350 [inline]
__do_sys_mount fs/namespace.c:4565 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4542
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f687ef9e559
RSP: 002b:00007f687fe79028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f687f225fa0 RCX: 00007f687ef9e559
RDX: 0000200000000ac0 RSI: 0000200000000a80 RDI: 0000200000000040
RBP: 00007f687f035ab8 R08: 0000200000000140 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f687f226038 R14: 00007f687f225fa0 R15: 00007ffcee9298a8
Showing all locks held in the system:
locks held by pr/ttyS0/16: 1, last CPU#1:
#0: ffffffff90033ed8 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
#0: ffffffff90033ed8 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:493 [inline]
#0: ffffffff90033ed8 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x30/0x60 kernel/printk/printk.c:291
locks held by khungtaskd/34: 1, last CPU#1:
#0: ffffffff9015a420 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff9015a420 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff9015a420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by kworker/u8:13/4657: 5, last CPU#0:
#0: ffff88813fe54148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88813fe54148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88813fe54148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#0: ffff88813fe54148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#1: ffffc9000f987c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc9000f987c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc9000f987c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#1: ffffc9000f987c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#2: ffffffff8ffe6190 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_disable+0x12/0x20 kernel/jump_label.c:247
#3: ffffffff9023baa0 (jump_label_mutex){+.+.}-{4:4}, at: jump_label_lock kernel/jump_label.c:27 [inline]
#3: ffffffff9023baa0 (jump_label_mutex){+.+.}-{4:4}, at: static_key_disable_cpuslocked+0x8d/0x1a0 kernel/jump_label.c:238
#4: ffffffff8fffd1e0 (text_mutex){+.+.}-{4:4}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145
locks held by syz-executor/5608: 4, last CPU#0:
#0: ffffffff90239530 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1541 [inline]
#0: ffffffff90239530 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x10a/0x470 kernel/fork.c:1594
#1: ffff88807e84e540 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:550 [inline]
#1: ffff88807e84e540 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x18a/0x1e10 mm/mmap.c:1716
#2: ffff88807b86d900 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:540 [inline]
#2: ffff88807b86d900 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x277/0x1e10 mm/mmap.c:1723
#3: ffffffff9015a420 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#3: ffffffff9015a420 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#3: ffffffff9015a420 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:302
locks held by udevd/5627: 1, on CPU#0:
#0: ffff888026d52350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:990
locks held by udevd/5628: 5, on CPU#0:
#0: ffff888024bfb9a8 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x7d0/0x1c10 security/integrity/ima/ima_main.c:319
#1: ffff88804364ef38 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xa4/0xca0 fs/seq_file.c:183
#2: ffff88802bd7a880 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5d/0x420 fs/kernfs/file.c:165
#3: ffff88802ba84c38 (kn->active#30){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#3: ffff88802ba84c38 (kn->active#30){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:166
#4: ffff88802a5521d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1109 [inline]
#4: ffff88802a5521d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
locks held by kworker/0:8/5780: 4, on CPU#0:
#0: ffff888024aa0d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff888024aa0d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff888024aa0d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#0: ffff888024aa0d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#1: ffffc90004f97c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90004f97c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90004f97c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#1: ffffc90004f97c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#2: ffff88802b5ef1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
#2: ffff88802b5ef1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4d30 drivers/usb/core/hub.c:5917
#3: ffff88802a5521d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
#3: ffff88802a5521d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073
locks held by syz.0.1192/9423: 2, on CPU#0:
#0: ffff88807a4260e8 (&type->s_umount_key#92/1){+.+.}-{4:4}, at: alloc_super fs/super.c:351 [inline]
#0: ffff88807a4260e8 (&type->s_umount_key#92/1){+.+.}-{4:4}, at: sget_fc+0x9cf/0x1a60 fs/super.c:874
#1: ffff888026d52350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:990
locks held by getty/11424: 2, on CPU#0:
#0: ffff88807ff9b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000384b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by syz.5.1933/11930: 2, on CPU#0:
#0: ffffffff916f0c28 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8fff4568 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xfc/0x2b0 kernel/umh.c:212
locks held by syz.3.1941/11947: 2, last CPU#0:
#0: ffff88807b86c080 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:550 [inline]
#0: ffff88807b86c080 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1ed/0x520 mm/util.c:579
#1: ffff88807ffce460 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2281 [inline]
#1: ffff88807ffce460 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Tainted: G S L syzkaller #0 PREEMPT(full)
Tainted: [S]=CPU_OUT_OF_SPEC, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 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+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:377 [inline]
watchdog+0x1073/0x10f0 kernel/hung_task.c:598
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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 S L syzkaller #0 PREEMPT(full)
Tainted: [S]=CPU_OUT_OF_SPEC, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:432
Code: 3b 3e fc 44 89 f9 d3 e5 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 5c 10 b4 fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc cc 44 89 f9 80 e1 07 38 c1
RSP: 0018:ffffc90000157970 EFLAGS: 00000006
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 00000000000003f9 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff858acb70 R12: dffffc0000000000
R13: 1ffffffff3842d8a R14: ffffffff9c216c40 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881234f7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd6175d9ff8 CR3: 000000000ff48000 CR4: 00000000003526f0
DR0: fffffffffeffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
serial_out drivers/tty/serial/8250/8250.h:139 [inline]
__serial8250_clear_IER drivers/tty/serial/8250/8250_port.c:-1 [inline]
serial8250_console_write+0x158/0x1200 drivers/tty/serial/8250/8250_port.c:3484
nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1
nbcon_emit_one kernel/printk/nbcon.c:1157 [inline]
nbcon_kthread_func+0x6d9/0x8d0 kernel/printk/nbcon.c:1271
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245