INFO: task syz.6.3121:16277 blocked for more than 143 seconds.
Not tainted 6.16.0-rc2-syzkaller-00318-g739a6c93cc75 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.3121 state:D stack:24168 pid:16277 tgid:16276 ppid:15441 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
request_wait_answer fs/fuse/dev.c:565 [inline]
__fuse_request_send fs/fuse/dev.c:579 [inline]
__fuse_simple_request+0xf15/0x18d0 fs/fuse/dev.c:673
fuse_simple_request fs/fuse/fuse_i.h:1237 [inline]
fuse_dentry_revalidate+0x48d/0x9e0 fs/fuse/dir.c:240
d_revalidate fs/namei.c:929 [inline]
lookup_fast+0x253/0x5b0 fs/namei.c:-1
walk_component+0x55/0x400 fs/namei.c:2134
lookup_last fs/namei.c:2639 [inline]
path_lookupat+0x163/0x430 fs/namei.c:2663
filename_lookup+0x212/0x570 fs/namei.c:2692
user_path_at+0x3a/0x60 fs/namei.c:3136
do_fchmodat+0xef/0x200 fs/open.c:694
__do_sys_chmod fs/open.c:720 [inline]
__se_sys_chmod fs/open.c:718 [inline]
__x64_sys_chmod+0x62/0x70 fs/open.c:718
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdb8cf8e929
RSP: 002b:00007fdb8de8b038 EFLAGS: 00000246 ORIG_RAX: 000000000000005a
RAX: ffffffffffffffda RBX: 00007fdb8d1b5fa0 RCX: 00007fdb8cf8e929
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000200000000280
RBP: 00007fdb8d010b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fdb8d1b5fa0 R15: 00007ffdb52b6e48
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5580:
#0: ffff88814c2af0a0
(&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036b42f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/0:4/5881:
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc900044cfbc0 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900044cfbc0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#2: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
3 locks held by kworker/u8:13/8952:
1 lock held by syz-executor/14343:
1 lock held by syz-executor/17229:
1 lock held by syz.5.3519/17828:
#0: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
3 locks held by syz.8.3521/17831:
#0: ffff88804bbd90a0 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:289 [inline]
#0: ffff88804bbd90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:335 [inline]
#0: ffff88804bbd90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline]
#0: ffff88804bbd90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_release+0x5c/0x200 drivers/tty/tty_ldisc.c:780
#1: ffff88804bbda0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: __tty_ldisc_lock_nested drivers/tty/tty_ldisc.c:295 [inline]
#1: ffff88804bbda0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:337 [inline]
#1: ffff88804bbda0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline]
#1: ffff88804bbda0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_release+0x80/0x200 drivers/tty/tty_ldisc.c:780
#2: ffffffff8e144780 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
6 locks held by syz-executor/17846:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-syzkaller-00318-g739a6c93cc75 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
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: 8952 Comm: kworker/u8:13 Not tainted 6.16.0-rc2-syzkaller-00318-g739a6c93cc75 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__lock_acquire+0x855/0xd20 kernel/locking/lockdep.c:-1
Code: 06 44 31 fe 01 ca 89 f0 c1 c0 08 29 f1 31 c8 01 d6 29 c2 89 c1 c1 c1 10 31 d1 01 f0 41 89 cf 41 c1 c7 13 29 ce 41 31 f7 01 c1 <44> 29 f8 44 01 f9 41 c1 c7 04 41 31 c7 49 c1 e7 20 49 09 cf 83 3d
RSP: 0018:ffffc9000217f8f0 EFLAGS: 00000007
RAX: 00000000f450bccc RBX: 0000000000000002 RCX: 000000001e7e131e
RDX: 00000000bc9c1a14 RSI: 000000007ddccfc9 RDI: ffff88802a3c5a00
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8b2d1062
R10: dffffc0000000000 R11: ffffffff8b2d0f90 R12: 0000000033262aed
R13: ffff88802a3c64f0 R14: ffff88802a3c6540 R15: 00000000cf4d9ea3
FS: 0000000000000000(0000) GS:ffff888125d85000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055dede0d5a00 CR3: 000000000df38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0xef/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245