INFO: task syz.3.7868:7411 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.3.7868 state:D stack:28712 pid:7411 tgid:7408 ppid:3639 task_flags:0x400140 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x169e/0x54f0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
fuse_chan_wait_aborted+0x15b/0x250 fs/fuse/dev.c:2212
fuse_conn_destroy+0x1e7/0x3e0 fs/fuse/inode.c:1969
fuse_sb_destroy fs/fuse/inode.c:1988 [inline]
fuse_kill_sb_anon+0x1ef/0x270 fs/fuse/inode.c:2001
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
get_signal+0x11eb/0x1330 kernel/signal.c:2809
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:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efea256c819
RSP: 002b:00007efea077c028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007efea27e6180 RCX: 00007efea256c819
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00002000000002c0
RBP: 00007efea2602c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efea27e6218 R14: 00007efea27e6180 R15: 00007ffdbbd17218
Showing all locks held in the system:
1 lock held by khungtaskd/39:
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
2 locks held by getty/5583:
#0: ffff8880296140a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
4 locks held by kworker/u8:2/21754:
#0: ffff888033caf138 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3280 [inline]
#0: ffff888033caf138 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0xa2e/0x1910 kernel/workqueue.c:3399
#1: ffffc9000ef8fc40 ((work_completion)(&(&forw_packet_aggr->delayed_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3281 [inline]
#1: ffffc9000ef8fc40 ((work_completion)(&(&forw_packet_aggr->delayed_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa69/0x1910 kernel/workqueue.c:3399
#2: ffff8880388a9110 (&hard_iface->bat_iv.ogm_buff_mutex){+.+.}-{4:4}, at: batadv_iv_ogm_schedule+0xef/0xf60 net/batman-adv/bat_iv_ogm.c:875
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:764 [inline]
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:836 [inline]
#3: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: batadv_iv_ogm_schedule+0x45c/0xf60 net/batman-adv/bat_iv_ogm.c:876
1 lock held by syz.3.7868/7411:
#0: ffff888035e180d0 (&type->s_umount_key#52){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888035e180d0 (&type->s_umount_key#52){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888035e180d0 (&type->s_umount_key#52){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
1 lock held by syz.4.8857/10883:
#0: ffff888056b98c68 (&sb->s_type->i_mutex_key#9/2){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1074 [inline]
#0: ffff888056b98c68 (&sb->s_type->i_mutex_key#9/2){+.+.}-{4:4}, at: __simple_recursive_removal+0x19a/0x520 fs/libfs.c:620
1 lock held by syz.0.8858/10886:
#0: ffff88803e8b00e8 (&kvm->slots_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#0: ffff88803e8b00e8 (&kvm->slots_lock){+.+.}-{4:4}, at: kvm_vm_ioctl_set_memory_region+0x5e/0xb0 virt/kvm/kvm_main.c:2146
1 lock held by syz.2.8859/10893:
#0: ffff88806011c0e8 (&kvm->slots_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#0: ffff88806011c0e8 (&kvm->slots_lock){+.+.}-{4:4}, at: kvm_vm_ioctl_set_memory_region+0x5e/0xb0 virt/kvm/kvm_main.c:2146
1 lock held by syz.1.8860/10898:
#0: ffff8880617540e8 (&kvm->slots_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#0: ffff8880617540e8 (&kvm->slots_lock){+.+.}-{4:4}, at: kvm_vm_ioctl_set_memory_region+0x5e/0xb0 virt/kvm/kvm_main.c:2146
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 10883 Comm: syz.4.8857 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:__lock_acquire+0x129/0x2cf0 kernel/locking/lockdep.c:-1
Code: c1 f8 03 48 be 29 5c 8f c2 f5 28 5c 8f 48 0f af f0 85 db 0f 85 52 01 00 00 85 ed 0f 84 4a 01 00 00 83 fd 31 0f 83 09 01 00 00 <48> 83 bc 24 20 01 00 00 00 0f 84 32 01 00 00 48 8b 44 24 08 48 05
RSP: 0018:ffffc90007e578c8 EFLAGS: 00000087
RAX: 0000000000000113 RBX: 0000000000000000 RCX: ffffffff93645330
RDX: 0000000000000002 RSI: 000000000000000b RDI: ffffffff8e3c8100
RBP: 0000000000000002 R08: 0000000000000000 R09: ffffffff8e3c8100
R10: 0000000000000000 R11: fffffbfff1f9e2ff R12: 0000000000000000
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f163b85e6c0(0000) GS:ffff888125b68000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3f67a89f00 CR3: 000000004c614000 CR4: 00000000003526f0
Call Trace:
reacquire_held_locks+0x104/0x190 kernel/locking/lockdep.c:5387
__lock_release kernel/locking/lockdep.c:5576 [inline]
lock_release+0x199/0x3c0 kernel/locking/lockdep.c:5891
rt_spin_unlock+0x29/0x200 kernel/locking/spinlock_rt.c:80
spin_unlock include/linux/spinlock_rt.h:109 [inline]
refill_stock+0x600/0x950 mm/memcontrol.c:2196
obj_cgroup_uncharge_pages mm/memcontrol.c:3039 [inline]
__refill_obj_stock+0x3bf/0x4b0 mm/memcontrol.c:3339
__memcg_slab_free_hook+0x2ed/0x4b0 mm/memcontrol.c:3528
memcg_slab_free_hook mm/slub.c:2488 [inline]
slab_free mm/slub.c:6243 [inline]
kfree+0x46d/0x6c0 mm/slub.c:6561
kvm_destroy_vm_debugfs virt/kvm/kvm_main.c:992 [inline]
kvm_destroy_vm virt/kvm/kvm_main.c:1261 [inline]
kvm_put_kvm+0x1d0/0xa50 virt/kvm/kvm_main.c:1331
kvm_vm_release+0x46/0x50 virt/kvm/kvm_main.c:1354
__fput+0x461/0xa70 fs/file_table.c:510
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:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f163d60c4ab
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007f163b85c450 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 0000200000000000 RCX: 00007f163d60c4ab
RDX: 00007f163b85cbd0 RSI: 000000004020ae46 RDI: 0000000000000008
RBP: 0000000000000008 R08: 0000000000000001 R09: 0000000000000050
R10: 0000000000000008 R11: 0000000000000246 R12: 00000000fec00000
R13: 00007f163b85cbd0 R14: 0000200000011000 R15: 0000000000000011