INFO: task syz.6.1270:10891 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1270 state:D stack:28784 pid:10891 ppid:7569 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
rwsem_down_read_slowpath+0x51a/0x880 kernel/locking/rwsem.c:1086
__down_read_common kernel/locking/rwsem.c:1250 [inline]
__down_read kernel/locking/rwsem.c:1263 [inline]
down_read+0x98/0x2e0 kernel/locking/rwsem.c:1522
__super_lock fs/super.c:58 [inline]
super_lock+0x17f/0x3a0 fs/super.c:117
super_lock_shared fs/super.c:146 [inline]
iterate_supers+0x80/0x170 fs/super.c:977
ksys_sync+0xa1/0x170 fs/sync.c:102
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f289779ce59
RSP: 002b:00007f2898584028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f2897a16090 RCX: 00007f289779ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f2897a16090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2897a16128 R14: 00007f2897a16090 R15: 00007ffc3598cc08
INFO: task syz.6.1270:10895 blocked for more than 146 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1270 state:D stack:28816 pid:10895 ppid:7569 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
rwsem_down_read_slowpath+0x51a/0x880 kernel/locking/rwsem.c:1086
__down_read_common kernel/locking/rwsem.c:1250 [inline]
__down_read kernel/locking/rwsem.c:1263 [inline]
down_read+0x98/0x2e0 kernel/locking/rwsem.c:1522
__super_lock fs/super.c:58 [inline]
super_lock+0x17f/0x3a0 fs/super.c:117
super_lock_shared fs/super.c:146 [inline]
iterate_supers+0x80/0x170 fs/super.c:977
ksys_sync+0xa1/0x170 fs/sync.c:102
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f289779ce59
RSP: 002b:00007f28959f6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f2897a16180 RCX: 00007f289779ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f2897a16180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2897a16218 R14: 00007f2897a16180 R15: 00007ffc3598cc08
Showing all locks held in the system:
2 locks held by kworker/0:0/8:
6 locks held by kworker/0:1/10:
#0: ffff888146674938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888146674938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc900000f7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc900000f7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#2: ffff8880253701d8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1094 [inline]
#2: ffff8880253701d8 (&dev->mutex){....}-{3:3}, at: hub_event+0x180/0x49f0 drivers/usb/core/hub.c:5861
#3: ffff888025373558 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3215 [inline]
#3: ffff888025373558 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5426 [inline]
#3: ffff888025373558 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5669 [inline]
#3: ffff888025373558 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5833 [inline]
#3: ffff888025373558 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x21d0/0x49f0 drivers/usb/core/hub.c:5915
#4: ffff888142fc0f68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5427 [inline]
#4: ffff888142fc0f68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5669 [inline]
#4: ffff888142fc0f68 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5833 [inline]
#4: ffff888142fc0f68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x21f8/0x49f0 drivers/usb/core/hub.c:5915
#5: ffffffff8dccc870 (ehci_cf_port_reset_rwsem){.+.+}-{3:3}, at: hub_port_reset+0x164/0x1730 drivers/usb/core/hub.c:3030
1 lock held by khungtaskd/29:
#0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by getty/5536:
#0: ffff8880318120a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217
1 lock held by syz-executor/6281:
#0: ffff8880580e00e0 (&type->s_umount_key#68){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff8880580e00e0 (&type->s_umount_key#68){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff8880580e00e0 (&type->s_umount_key#68){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
2 locks held by kworker/u4:17/9341:
1 lock held by syz.6.1270/10891:
#0: ffff8880580e00e0 (&type->s_umount_key#68){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880580e00e0 (&type->s_umount_key#68){++++}-{3:3}, at: super_lock+0x17f/0x3a0 fs/super.c:117
1 lock held by syz.6.1270/10895:
#0: ffff8880580e00e0 (&type->s_umount_key#68){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880580e00e0 (&type->s_umount_key#68){++++}-{3:3}, at: super_lock+0x17f/0x3a0 fs/super.c:117
2 locks held by syz.2.1969/12978:
#0: ffffffff976a3458 (nfnl_subsys_ipset){+.+.}-{3:3}, at: call_ad+0x28d/0xb40 net/netfilter/ipset/ip_set_core.c:1746
#1: ffffffff8d137b38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
#1: ffffffff8d137b38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x306/0x880 kernel/rcu/tree_exp.h:1004
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf3d/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 9341 Comm: kworker/u4:17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:504 [inline]
RIP: 0010:is_cpu_allowed+0x4b/0x1e0 kernel/sched/core.c:2469
Code: 89 f8 48 c1 e8 03 80 3c 28 00 74 08 4c 89 ff e8 1b 91 80 00 4d 8b 3f 83 fb 08 0f 83 31 01 00 00 41 89 dc 41 89 dd 41 c1 ed 06 <4b> 8d 3c ef be 08 00 00 00 e8 b7 92 80 00 4d 0f a3 27 0f 83 de 00
RSP: 0018:ffffc900001f0c70 EFLAGS: 00000046
RAX: 1ffff1100579b083 RBX: 0000000000000001 RCX: b060858372545500
RDX: 0000000000000006 RSI: 0000000000000001 RDI: ffff88802bcd8000
RBP: dffffc0000000000 R08: ffffffff8e8b666f R09: 1ffffffff1d16ccd
R10: dffffc0000000000 R11: fffffbfff1d16cce R12: 0000000000000001
R13: 0000000000000000 R14: ffff88802bcd8000 R15: ffff88802bcd8428
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005646e9478130 CR3: 000000007e524000 CR4: 00000000003506e0
Call Trace:
select_task_rq kernel/sched/core.c:3644 [inline]
try_to_wake_up+0x4d5/0x1190 kernel/sched/core.c:4334
autoremove_wake_function+0x17/0x100 kernel/sched/wait.c:424
__wake_up_common+0x2a4/0x4e0 kernel/sched/wait.c:107
__wake_up_common_lock kernel/sched/wait.c:138 [inline]
__wake_up+0x125/0x1a0 kernel/sched/wait.c:160
irq_work_single+0xd5/0x230 kernel/irq_work.c:221
irq_work_run_list kernel/irq_work.c:252 [inline]
irq_work_run+0x15d/0x2f0 kernel/irq_work.c:261
__sysvec_irq_work+0x98/0x370 arch/x86/kernel/irq_work.c:22
instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
sysvec_irq_work+0x9c/0xc0 arch/x86/kernel/irq_work.c:17
asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:723
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline]
RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:196
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 db 55 24 03 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc900046d76f8 EFLAGS: 00000246
RAX: 00000000000000f6 RBX: 0000000000000200 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
RBP: 0000000000000000 R08: ffffc900046d7667 R09: 1ffff920008daecc
R10: dffffc0000000000 R11: fffff520008daecd R12: 0000000000000001
R13: 0000000000000001 R14: ffffffff8d22e748 R15: 0000000000000020
__apic_send_IPI_self arch/x86/include/asm/apic.h:454 [inline]
arch_irq_work_raise+0x68/0x70 arch/x86/kernel/irq_work.c:31
irq_work_queue+0x99/0x140 kernel/irq_work.c:124
__kfence_alloc+0x2a0/0x3d0 mm/kfence/core.c:1126
kfence_alloc include/linux/kfence.h:129 [inline]
slab_alloc_node mm/slub.c:3481 [inline]
kmem_cache_alloc_node+0x2b4/0x320 mm/slub.c:3540
__alloc_skb+0x103/0x2c0 net/core/skbuff.c:643
alloc_skb include/linux/skbuff.h:1316 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x293/0xb10 drivers/net/netdevsim/dev.c:851
process_one_work kernel/workqueue.c:2653 [inline]
process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293