INFO: task syz.5.1992:15033 blocked for more than 147 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1992 state:D stack:27016 pid:15033 ppid:9029 flags:0x00004006
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
request_wait_answer fs/fuse/dev.c:407 [inline]
__fuse_request_send fs/fuse/dev.c:426 [inline]
fuse_simple_request+0x1204/0x1c70 fs/fuse/dev.c:513
fuse_flush+0x667/0x8b0 fs/fuse/file.c:549
filp_flush fs/open.c:1533 [inline]
filp_close+0xb1/0x150 fs/open.c:1546
__range_close fs/file.c:698 [inline]
__close_range+0x368/0x660 fs/file.c:755
__do_sys_close_range fs/open.c:1599 [inline]
__se_sys_close_range fs/open.c:1596 [inline]
__x64_sys_close_range+0x7a/0x90 fs/open.c:1596
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: 0033:0x7f4f5759ce59
RSP: 002b:00007ffdf03548c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007ffdf03549b0 RCX: 00007f4f5759ce59
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00000000000ecd37 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2f020000 R11: 0000000000000246 R12: 00007ffdf03549f0
R13: 00007f4f57815fac R14: 00000000000ed30c R15: 00007f4f57815fa0
Showing all locks held in the system:
2 locks held by kworker/u4:0/11:
#0: ffff8880b8e3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559
#1: ffff8880b8e289c0 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffff8880b8e289c0 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2176/0x45a0 kernel/sched/core.c:6695
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/5528:
#0: ffff88802ccee0a0 (&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
3 locks held by kworker/0:4/5823:
3 locks held by kworker/u4:20/6122:
#0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc9000b4bfd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000b4bfd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#2: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286
2 locks held by kworker/0:2/15550:
#0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc9000dbdfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000dbdfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
2 locks held by syz.6.2220/16038:
#0: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3511
#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
3 locks held by syz.4.2222/16047:
#0: ffff8880781dca20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#0: ffff8880781dca20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
#0: ffff8880781dca20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x9b/0x230 net/socket.c:1420
#1: ffff88807cc0a130 (sk_lock-AF_CAN){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#1: ffff88807cc0a130 (sk_lock-AF_CAN){+.+.}-{0:0}, at: bcm_release+0x1cd/0x860 net/can/bcm.c:1563
#2: ffffffff8d137b38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#2: ffffffff8d137b38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
3 locks held by kvm-nx-lpage-re/16048:
#0: ffffffff8d15bc08 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:369 [inline]
#0: ffffffff8d15bc08 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_attach_task_all+0x26/0xe0 kernel/cgroup/cgroup-v1.c:61
#1: ffffffff8cfcd330 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock+0x11/0x30 kernel/cgroup/cgroup.c:2414
#2: ffffffff8d15bdf0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_task_all+0x30/0xe0 kernel/cgroup/cgroup-v1.c:62
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15853 Comm: udevd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:127 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:178 [inline]
RIP: 0010:kasan_check_range+0x89/0x290 mm/kasan/generic.c:187
Code: 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 3d 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 <0f> 85 8d 01 00 00 49 ff c3 48 ff c3 75 ee e9 1d 01 00 00 44 89 dd
RSP: 0018:ffffc9001f8d7408 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffffffffffffffff RCX: ffffffff81683ba4
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff911c75a8
RBP: ffffc9001f8d7688 R08: ffffffff911c75af R09: 1ffffffff2238eb5
R10: dffffc0000000000 R11: fffffbfff2238eb5 R12: 0000000000000001
R13: ffff88802c430000 R14: fffffbfff2238eb6 R15: 1ffffffff2238eb5
FS: 00007f0604c16880(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f23371ea2f8 CR3: 000000007b4f8000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
instrument_atomic_read include/linux/instrumented.h:68 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
hlock_class kernel/locking/lockdep.c:228 [inline]
check_wait_context kernel/locking/lockdep.c:4774 [inline]
__lock_acquire+0x624/0x7d40 kernel/locking/lockdep.c:5087
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
down_write+0x97/0x200 kernel/locking/rwsem.c:1573
inode_lock include/linux/fs.h:804 [inline]
do_truncate+0x19c/0x240 fs/open.c:64
handle_truncate fs/namei.c:3299 [inline]
do_open fs/namei.c:3644 [inline]
path_openat+0x2a32/0x3230 fs/namei.c:3797
do_filp_open+0x1f5/0x430 fs/namei.c:3824
do_sys_openat2+0x134/0x1d0 fs/open.c:1421
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1447
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: 0033:0x7f06044a7407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffd3360ee00 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0604c16880 RCX: 00007f06044a7407
RDX: 00000000000a0241 RSI: 00007ffd3360fac0 RDI: ffffffffffffff9c
RBP: 000055ca8770b0c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000124 R11: 0000000000000202 R12: 000055ca876dee00
R13: 00007ffd3360fac0 R14: 00007ffd3360f6c0 R15: 00007ffd3360f2c0