INFO: task syz.0.601:7952 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.0.601 state:D stack:28408 pid:7952 tgid:7942 ppid:5623 task_flags:0x400640 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2e7/0x4c0 kernel/sched/completion.c:121
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:269
coredump_wait fs/coredump.c:537 [inline]
vfs_coredump+0x80d/0x5770 fs/coredump.c:1202
get_signal+0x2162/0x2210 kernel/signal.c:3023
arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x98/0x670 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5340d9ce59
RSP: 002b:00007f5341d21028 EFLAGS: 00000246 ORIG_RAX: 00000000000000c8
RAX: 0000000000000000 RBX: 00007f5341016090 RCX: 00007f5340d9ce59
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 000000000000015f
RBP: 00007f5340e32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5341016128 R14: 00007f5341016090 R15: 00007ffd389f5e18
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e7e5560 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e7e5560 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e7e5560 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by getty/5373:
#0: ffff8880333be0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211
6 locks held by kworker/1:4/5616:
#0: ffff888020ec8940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
#1: ffffc90003ba7d08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
#2: ffff88802b0821d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#2: ffff88802b0821d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
#3: ffff88803540c1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#3: ffff88803540c1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076
#4: ffff88802d99f1a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#4: ffff88802d99f1a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076
#5: ffff88802af03f60 (hcd->bandwidth_mutex){+.+.}-{4:4}, at: usb_set_interface+0x294/0xe20 drivers/usb/core/message.c:1624
3 locks held by kworker/0:2H/5893:
4 locks held by udevd/7005:
#0: ffff8880763dc098 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
#1: ffff888028faf880 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
#2: ffff88803404db48 (kn->active#26){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff88803404db48 (kn->active#26){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
#3: ffff88803540c1d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1045 [inline]
#3: ffff88803540c1d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
3 locks held by syz.3.1112/9772:
#0: ffffffff904edb80 (register_mutex#4){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#0: ffffffff904edb80 (register_mutex#4){+.+.}-{4:4}, at: odev_release+0x44/0x70 sound/core/seq/oss/seq_oss.c:140
#1: ffff88803549d4b0 (&mdev->open_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#1: ffff88803549d4b0 (&mdev->open_mutex){+.+.}-{4:4}, at: snd_seq_oss_midi_close+0xb6/0x4c0 sound/core/seq/oss/seq_oss_midi.c:373
#2: ffff88802bfd59e0 (&grp->list_mutex){++++}-{4:4}, at: class_rwsem_write_constructor include/linux/rwsem.h:270 [inline]
#2: ffff88802bfd59e0 (&grp->list_mutex){++++}-{4:4}, at: snd_seq_port_disconnect+0x4c/0x650 sound/core/seq/seq_ports.c:625
1 lock held by syz.1.1115/9785:
#0: ffff88807bf724d0 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x35/0x140 net/netfilter/nf_tables_api.c:11490
2 locks held by syz.1.1115/9797:
#0: ffffffff9b5f0b40 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:96 [inline]
#0: ffffffff9b5f0b40 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnetlink_rcv_batch+0x281/0x2880 net/netfilter/nfnetlink.c:392
#1: ffff88807bf724d0 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x35/0x140 net/netfilter/nf_tables_api.c:11490
1 lock held by syz.1.1115/9798:
#0: ffffffff9b5f0b40 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:96 [inline]
#0: ffffffff9b5f0b40 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnetlink_rcv_batch+0x281/0x2880 net/netfilter/nfnetlink.c:392
6 locks held by syz.5.1116/9788:
#0: ffff888078831270 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1261
#1: ffff88807bab0410 (sb_writers#11){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:740
#2: ffff8880570e3880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343
#3: ffffffff8e849b20 (cgroup_mutex){+.+.}-{4:4}, at: cgroup_lock include/linux/cgroup.h:456 [inline]
#3: ffffffff8e849b20 (cgroup_mutex){+.+.}-{4:4}, at: cgroup_kn_lock_live+0x116/0x520 kernel/cgroup/cgroup.c:1683
#4: ffffffff8e67c630 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2501 [inline]
#4: ffffffff8e67c630 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x567/0x890 kernel/cgroup/cgroup.c:3066
#5: ffffffff8e849890 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2507 [inline]
#5: ffffffff8e849890 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x573/0x890 kernel/cgroup/cgroup.c:3066
1 lock held by syz.2.1117/9789:
#0: ffff8880748d4180 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
#0: ffff8880748d4180 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x260 net/socket.c:721
2 locks held by syz.2.1117/9794:
#0: ffff8880575052c0 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
#0: ffff8880575052c0 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x260 net/socket.c:721
#1: ffffffff8e7f10a8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
=============================================
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 05/09/2026
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: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: 8058 Comm: kworker/u8:11 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline]
RIP: 0010:stack_access_ok+0x76/0x1d0 arch/x86/kernel/unwind_orc.c:409
Code: c1 ea 03 80 3c 02 00 0f 85 24 01 00 00 48 8d 7b 10 4c 8b 6b 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 0b 01 00 00 48 8b 43 10 49 39 ed 77 1a 48 39 e8 76 15 4a 8d
RSP: 0018:ffffc9000db776b0 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffffc9000db77750 RCX: ffffffff9184a33e
RDX: 1ffff92001b6eeec RSI: ffffc9000db77a98 RDI: ffffc9000db77760
RBP: ffffc9000db77a98 R08: ffffffff9184a342 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000017665 R12: 0000000000000008
R13: ffffc9000db70000 R14: ffffc9000db77aa0 R15: ffffc9000db77784
FS: 0000000000000000(0000) GS:ffff888124387000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2eefdff8 CR3: 000000000e596000 CR4: 00000000003526f0
Call Trace:
deref_stack_reg arch/x86/kernel/unwind_orc.c:419 [inline]
unwind_next_frame+0xcf5/0x2090 arch/x86/kernel/unwind_orc.c:614
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2689 [inline]
slab_free mm/slub.c:6251 [inline]
kmem_cache_free+0x127/0x6c0 mm/slub.c:6378
kfree_skbmem+0x19a/0x210 net/core/skbuff.c:1137
__kfree_skb net/core/skbuff.c:1204 [inline]
consume_skb net/core/skbuff.c:1436 [inline]
consume_skb+0xd1/0x110 net/core/skbuff.c:1430
nsim_dev_trap_report drivers/net/netdevsim/dev.c:892 [inline]
nsim_dev_trap_report_work+0x8de/0xd20 drivers/net/netdevsim/dev.c:922
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314
process_scheduled_works kernel/workqueue.c:3397 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478
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