INFO: task syz.4.14986:6580 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.4.14986 state:D stack:27784 pid:6580 tgid:6579 ppid:6375 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7004
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
sync_bdevs+0x153/0x480 block/bdev.c:1304
ksys_sync+0xb0/0xf0 fs/sync.c:105
__do_sys_sync+0xe/0x20 fs/sync.c:111
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8ed3d9c629
RSP: 002b:00007f8ed1ff6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f8ed4015fa0 RCX: 00007f8ed3d9c629
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f8ed4015fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8ed4016038 R14: 00007f8ed4015fa0 R15: 00007ffd0900e818
Showing all locks held in the system:
5 locks held by kworker/0:1/10:
#0: ffff8880226cdd48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
#1: ffffc900000f7d08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
#2: ffff88802b31a198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#2: ffff88802b31a198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
#3: ffff888069909198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#3: ffff888069909198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1008
#4: ffff8880216f1160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#4: ffff8880216f1160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1008
1 lock held by khungtaskd/31:
#0: ffffffff8e7e93e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7e93e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7e93e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by getty/5567:
#0: ffff888033b480a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900033332f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
1 lock held by udevd/16682:
#0: ffff888027c5d358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961
1 lock held by syz.4.14986/6580:
#0: ffff888027c5d358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1304
1 lock held by syz.6.15438/7729:
#0: ffff888027c5d358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1304
1 lock held by syz.6.15438/7731:
#0: ffff888027c5d358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1304
1 lock held by syz.6.15438/7732:
#0: ffff888027c5d358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1304
1 lock held by syz.6.15438/7733:
#0: ffff888027c5d358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1304
1 lock held by syz.6.15438/7736:
#0: ffff888027c5d358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1304
1 lock held by syz.6.15438/7737:
#0: ffff888027c5d358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1304
1 lock held by syz.8.17121/12403:
#0: ffff888037020260 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
#0: ffff888037020260 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sockopt_lock_sock net/core/sock.c:1152 [inline]
#0: ffff888037020260 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sockopt_lock_sock+0x59/0x70 net/core/sock.c:1143
1 lock held by syz.8.17121/12405:
#0: ffff888037020260 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
#0: ffff888037020260 (sk_lock-AF_INET6){+.+.}-{0:0}, at: udpv6_sendmsg+0x1d67/0x2f60 net/ipv6/udp.c:1738
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [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:346 [inline]
watchdog+0xd25/0x1050 kernel/hung_task.c:515
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6490 Comm: kworker/0:9 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events dvb_usb_read_remote_control
RIP: 0010:kasan_mem_to_shadow include/linux/kasan.h:66 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline]
RIP: 0010:kasan_check_range+0x61/0x1e0 mm/kasan/generic.c:200
Code: 00 80 ff ff 48 39 c7 0f 82 c2 00 00 00 4c 8d 54 37 ff 48 89 fd 48 b8 00 00 00 00 00 fc ff df 4d 89 d1 48 c1 ed 03 49 c1 e9 03 <48> 01 c5 49 01 c1 48 89 e8 49 8d 59 01 48 89 da 48 29 ea 48 83 fa
RSP: 0018:ffffc90000007d08 EFLAGS: 00000803
RAX: dffffc0000000000 RBX: ffff888075ab0000 RCX: ffffffff81d5deb2
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90d95bf8
RBP: 1ffffffff21b2b7f R08: 0000000000000000 R09: 1ffffffff21b2b7f
R10: ffffffff90d95bff R11: 0000000000000001 R12: 0000000000000088
R13: 0000000000000000 R14: 0000000000000000 R15: ffff888075ab0a37
FS: 0000000000000000(0000) GS:ffff88812434a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcab51e82f8 CR3: 00000000266f7000 CR4: 00000000003526f0
Call Trace:
instrument_atomic_read include/linux/instrumented.h:82 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
cpumask_test_cpu include/linux/cpumask.h:649 [inline]
cpu_active include/linux/cpumask.h:1251 [inline]
ttwu_queue_cond kernel/sched/core.c:3863 [inline]
ttwu_queue_wakelist+0x72/0x430 kernel/sched/core.c:3899
ttwu_queue kernel/sched/core.c:3913 [inline]
try_to_wake_up+0xb35/0x1a80 kernel/sched/core.c:4242
hrtimer_wakeup+0x47/0x60 kernel/time/hrtimer.c:2021
__run_hrtimer kernel/time/hrtimer.c:1785 [inline]
__hrtimer_run_queues+0x50e/0xa70 kernel/time/hrtimer.c:1849
hrtimer_interrupt+0x397/0x8c0 kernel/time/hrtimer.c:1911
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x109/0x490 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline]
RIP: 0010:vprintk_emit+0x553/0x6b0 kernel/printk/printk.c:2478
Code: 00 4d 85 ed 0f 85 1b 01 00 00 e8 08 16 21 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 d6 10 21 00 48 85 ed 0f 85 27 01 00 00 e8 15 21 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00
RSP: 0018:ffffc9000379faa8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 000000000000003e RCX: ffffffff81e7854a
RDX: ffff88802c4ec900 RSI: ffffffff81e78554 RDI: ffff88802c4ec900
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff920006f3f57
R13: 0000000000000200 R14: ffff88802029c900 R15: ffffc9000379fb70
_printk+0xcf/0x110 kernel/printk/printk.c:2504
dvb_usb_read_remote_control.cold+0x13/0x18 drivers/media/usb/dvb-usb/dvb-usb-remote.c:263
process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275
process_scheduled_works kernel/workqueue.c:3358 [inline]
worker_thread+0x5da/0xe40 kernel/workqueue.c:3439
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245