INFO: task syz.2.1386:10434 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1386 state:D stack:25760 pid:10434 tgid:10434 ppid:5831 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6908
__schedule_loop kernel/sched/core.c:6990 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7005
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7062
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
bdev_release+0x1a9/0x650 block/bdev.c:1144
blkdev_release+0x15/0x20 block/fops.c:705
__fput+0x44f/0xa70 fs/file_table.c:469
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f660319c799
RSP: 002b:00007ffed9229548 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f6603417da0 RCX: 00007f660319c799
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f6603417da0 R08: 0000000000000006 R09: 0000000000000000
R10: 00007f6603417cb0 R11: 0000000000000246 R12: 0000000000064980
R13: 00007f6603415fac R14: 00000000000646b0 R15: 00007ffed9229650
INFO: task syz.2.1386:10436 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1386 state:D stack:27056 pid:10436 tgid:10434 ppid:5831 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6908
__schedule_loop kernel/sched/core.c:6990 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7005
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7062
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
bdev_release+0x1a9/0x650 block/bdev.c:1144
blkdev_release+0x15/0x20 block/fops.c:705
__fput+0x44f/0xa70 fs/file_table.c:469
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f660319c799
RSP: 002b:00007f6604091028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f6603415fa0 RCX: 00007f660319c799
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000004
RBP: 00007f6603232bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6603416038 R14: 00007f6603415fa0 R15: 00007ffed92293e8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e760620 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e760620 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e760620 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:2/36:
#0: ffff8880320ba948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254
#1: ffffc90000ac7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255
#2: ffffffff8fbd3188 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8fbd3188 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11e/0x14c0 net/ipv6/addrconf.c:4198
2 locks held by getty/5579:
#0: ffff8880374710a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900033332f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by syz-executor/5818:
#0: ffff88807b788ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff88807b788ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff88807b7880c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346
#2: ffffffff8e7668b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8e7668b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
2 locks held by kworker/1:5/5881:
#0: ffff88801b057548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254
#1: ffffc9000404fc40 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255
1 lock held by syz.3.369/6918:
1 lock held by udevd/9321:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961
1 lock held by syz.2.1386/10434:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1144
1 lock held by syz.2.1386/10436:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1144
1 lock held by syz.5.1776/11815:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.5.1776/11817:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.5.1776/11821:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.5.1776/11824:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.1.1789/11878:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.1.1789/11880:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.1.1789/11883:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.1.1789/11886:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.4.1850/12198:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.4.1850/12199:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.4.1850/12200:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.4.1850/12201:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.7.1886/12360:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.7.1886/12362:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.7.1886/12363:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
1 lock held by syz.7.1886/12365:
#0: ffff88802757e358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304
2 locks held by syz.6.1889/12398:
#0: ffff8880550f00e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880550f00e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880550f00e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffffffff8e7668b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8e7668b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
2 locks held by syz.0.1892/12404:
#0: ffffffff8fbd3188 (rtnl_mutex){+.+.}-{4:4}, at: bpf_xdp_link_attach+0x121/0x980 net/core/dev.c:10666
#1: ffffffff8fbd6928 (bpf_dispatcher_xdp.mutex){+.+.}-{4:4}, at: bpf_dispatcher_change_prog+0xc6/0xd70 kernel/bpf/dispatcher.c:146
1 lock held by syz.0.1892/12405:
#0: ffffffff8fbd3188 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8fbd3188 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8fbd3188 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink+0x42a/0x820 net/core/rtnetlink.c:3562
1 lock held by dhcpcd/12414:
#0: ffff888077d9ca48 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff888077d9ca48 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: __sock_release+0x89/0x250 net/socket.c:730
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 12398 Comm: syz.6.1889 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:get_stack_info_noinstr+0xf7/0x130 arch/x86/kernel/dumpstack_64.c:189
Code: d7 40 0f 92 c6 49 39 cf 40 0f 93 c7 40 08 f7 75 27 41 c7 06 02 00 00 00 49 89 56 08 49 89 4e 10 48 8b 00 49 89 46 18 89 d8 5b <41> 5c 41 5d 41 5e 41 5f e9 7c 19 03 00 cc 4c 89 ff 4c 89 f6 5b 41
RSP: 0018:ffffc9001bf9f570 EFLAGS: 00000202
RAX: 000000001bf9f601 RBX: ffffc9001bf9f648 RCX: ffffc9001bf98000
RDX: ffffc9001bf9f628 RSI: ffffc9001bfa0000 RDI: ffffc9001bf9f5c8
RBP: ffffc9001bf9f601 R08: ffffc9001bf9f601 R09: 0000000000000000
R10: ffffc9001bf9f628 R11: fffff520037f3ed1 R12: ffff88807f7cbd00
R13: ffffc9001bf9f648 R14: ffffc9001bf9f628 R15: ffffc9001bf9f5c8
FS: 0000000000000000(0000) GS:ffff888125557000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd22194818 CR3: 0000000037ef0000 CR4: 00000000003526f0
Call Trace:
get_stack_info+0x3a/0xf0 arch/x86/kernel/dumpstack_64.c:199
__unwind_start+0x43e/0x760 arch/x86/kernel/unwind_orc.c:742
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1436 [inline]
__free_frozen_pages+0xbe2/0xd60 mm/page_alloc.c:2981
vfree+0x1e9/0x3d0 mm/vmalloc.c:3472
kcov_put kernel/kcov.c:442 [inline]
kcov_close+0x28/0x50 kernel/kcov.c:543
__fput+0x44f/0xa70 fs/file_table.c:469
task_work_run+0x1d9/0x270 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x70f/0x23c0 kernel/exit.c:974
do_group_exit+0x21b/0x2d0 kernel/exit.c:1116
get_signal+0x1284/0x1330 kernel/signal.c:3032
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd8df19c799
Code: Unable to access opcode bytes at 0x7fd8df19c76f.
RSP: 002b:00007fd8dffd00e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fd8df416188 RCX: 00007fd8df19c799
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd8df416188
RBP: 00007fd8df416180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd8df416218 R14: 00007ffe355e0940 R15: 00007ffe355e0a28