INFO: task syz.2.6492:32104 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.2.6492 state:D stack:28856 pid:32104 tgid:32100 ppid:29844 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xccc/0x1bd0 kernel/locking/mutex.c:821
blk_debugfs_lock_nomemsave block/blk.h:787 [inline]
blk_trace_remove kernel/trace/blktrace.c:561 [inline]
blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
blkdev_common_ioctl+0x170c/0x2b80 block/ioctl.c:717
blkdev_ioctl+0x43b/0x6f0 block/ioctl.c:791
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6e5799de99
RSP: 002b:00007f6e587c9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f6e57c26090 RCX: 00007f6e5799de99
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f6e57a33eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6e57c26128 R14: 00007f6e57c26090 R15: 00007ffd69aed718
Showing all locks held in the system:
5 locks held by kworker/1:0/24:
#0: ffff888023ed4540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc900001e7d08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88802cc3a1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88802cc3a1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4a60 drivers/usb/core/hub.c:5899
#3: ffff88802cc3f568 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline]
#3: ffff88802cc3f568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline]
#3: ffff88802cc3f568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
#3: ffff88802cc3f568 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
#3: ffff88802cc3f568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2b25/0x4a60 drivers/usb/core/hub.c:5953
#4: ffff88802cb81060 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline]
#4: ffff88802cb81060 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
#4: ffff88802cb81060 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
#4: ffff88802cb81060 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2b4e/0x4a60 drivers/usb/core/hub.c:5953
1 lock held by khungtaskd/31:
#0: ffffffff8ebe6180 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8ebe6180 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8ebe6180 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by kswapd0/84:
1 lock held by kswapd1/85:
2 locks held by klogd/4965:
#0: ffffffff8edb81a0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4402 [inline]
#0: ffffffff8edb81a0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4427 [inline]
#0: ffffffff8edb81a0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath mm/page_alloc.c:4876 [inline]
#0: ffffffff8edb81a0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_frozen_pages_noprof+0x13f2/0x2dc0 mm/page_alloc.c:5317
#1: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:675 [inline]
#1: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:659
2 locks held by getty/5363:
#0: ffff888033fa00a0 (&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
3 locks held by syz-executor/25229:
3 locks held by udevd/29781:
#0: ffffffff8edb81a0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4402 [inline]
#0: ffffffff8edb81a0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4427 [inline]
#0: ffffffff8edb81a0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath mm/page_alloc.c:4876 [inline]
#0: ffffffff8edb81a0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_frozen_pages_noprof+0x13f2/0x2dc0 mm/page_alloc.c:5317
#1: ffffe8ffffc26528 (&acomp_ctx->mutex){+.+.}-{4:4}, at: zswap_compress mm/zswap.c:853 [inline]
#1: ffffe8ffffc26528 (&acomp_ctx->mutex){+.+.}-{4:4}, at: zswap_store_page mm/zswap.c:1410 [inline]
#1: ffffe8ffffc26528 (&acomp_ctx->mutex){+.+.}-{4:4}, at: zswap_store+0xd16/0x2e70 mm/zswap.c:1521
#2: ffff8880b8424568 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:218 [inline]
#2: ffff8880b8424568 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2e8e/0x6730 kernel/sched/core.c:7228
3 locks held by syz.2.6492/32101:
1 lock held by syz.2.6492/32104:
#0: ffff8880279391f8 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:787 [inline]
#0: ffff8880279391f8 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880279391f8 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
2 locks held by syz.1.6665/377:
#0: ffff888028627868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:787 [inline]
#0: ffff888028627868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:801 [inline]
#0: ffff888028627868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
#1: ffffffff8ec734a0 (relay_channels_mutex){+.+.}-{4:4}, at: relay_open+0x3a2/0xa00 kernel/relay.c:515
1 lock held by syz.1.6665/383:
#0: ffff888028627868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:787 [inline]
#0: ffff888028627868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff888028627868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.4.6884/1338:
#0: ffff88801bc35cf8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:601 [inline]
#0: ffff88801bc35cf8 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:450 [inline]
#0: ffff88801bc35cf8 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x160/0x6f0 mm/mmap_lock.c:501
1 lock held by syz.4.6884/1339:
#0: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:675 [inline]
#0: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:659
5 locks held by syz.4.6884/1355:
=============================================
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 06/10/2026
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+0x21c/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+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 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: 25582 Comm: kworker/0:1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
Workqueue: events legacy_dvb_usb_read_remote_control
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x41/0xc0 kernel/rcu/tree.c:752
Code: 64 94 89 c5 83 f8 07 0f 87 82 00 00 00 48 8d 3c ed 20 b9 46 8e 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <75> 5c 48 03 1c ed 20 b9 46 8e 48 b8 00 00 00 00 00 fc ff df 48 89
RSP: 0018:ffffc900000079a0 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffffffff9464bc68 RCX: ffff8880502dca80
RDX: 1ffffffff1c8d724 RSI: ffffffff8c401200 RDI: ffffffff8e46b920
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffed1003e5792f
R10: ffff88801f2bc97f R11: 0000000000000000 R12: ffff88801f2bc800
R13: ffff88801f2bc800 R14: 0000000000000001 R15: 0000000000000008
FS: 0000000000000000(0000) GS:ffff888123de8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb2409ed2f8 CR3: 0000000054e6d000 CR4: 00000000003526f0
Call Trace:
rcu_read_lock_held_common kernel/rcu/update.c:109 [inline]
rcu_read_lock_any_held+0x22/0xa0 kernel/rcu/update.c:384
select_idle_sibling kernel/sched/fair.c:8895 [inline]
select_task_rq_fair+0x2c06/0x5400 kernel/sched/fair.c:9606
select_task_rq kernel/sched/core.c:3619 [inline]
try_to_wake_up+0xaa2/0x1c90 kernel/sched/core.c:4393
call_timer_fn+0x19a/0x610 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers+0x757/0xb00 kernel/time/timer.c:2374
__run_timer_base kernel/time/timer.c:2386 [inline]
__run_timer_base kernel/time/timer.c:2378 [inline]
run_timer_base+0x114/0x190 kernel/time/timer.c:2395
run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2405
handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
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 98 ab 21 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 26 a6 21 00 48 85 ed 0f 85 27 01 00 00 78 ab 21 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00
RSP: 0018:ffffc90004e47a18 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 000000000000003a RCX: ffffffff81e8323a
RDX: ffff88802d3c8000 RSI: ffffffff81e83244 RDI: ffff88802d3c8000
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff920009c8f45
R13: 0000000000000200 R14: ffff88801f690000 R15: ffffc90004e47ae0
_printk+0xcf/0x110 kernel/printk/printk.c:2504
legacy_dvb_usb_read_remote_control.cold+0x11/0x16 drivers/media/usb/dvb-usb/dvb-usb-remote.c:124
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245