INFO: task syz.4.162:6692 blocked for more than 143 seconds.
Not tainted 6.16.0-rc6-next-20250718-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.162 state:D stack:27176 pid:6692 tgid:6690 ppid:5859 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5351 [inline]
__schedule+0x1737/0x4d30 kernel/sched/core.c:6954
__schedule_loop kernel/sched/core.c:7036 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7051
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7108
rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1187
__down_write_common kernel/locking/rwsem.c:1319 [inline]
__down_write kernel/locking/rwsem.c:1328 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1593
mmap_write_lock include/linux/mmap_lock.h:356 [inline]
do_mbind mm/mempolicy.c:1460 [inline]
kernel_mbind mm/mempolicy.c:1682 [inline]
__do_sys_mbind mm/mempolicy.c:1756 [inline]
__se_sys_mbind+0x613/0xc30 mm/mempolicy.c:1752
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: 0033:0x7f137438e9a9
RSP: 002b:00007f1375298038 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed
RAX: ffffffffffffffda RBX: 00007f13745b5fa0 RCX: 00007f137438e9a9
RDX: 0000000000008003 RSI: 0000000000600000 RDI: 0000200000000000
RBP: 00007f1374410d69 R08: 0000000000000006 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f13745b5fa0 R15: 00007ffcfaf9e7f8
INFO: task syz.4.162:6719 blocked for more than 144 seconds.
Not tainted 6.16.0-rc6-next-20250718-syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.162 state:D stack:28872 pid:6719 tgid:6690 ppid:5859 task_flags:0x40044c flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5351 [inline]
__schedule+0x1737/0x4d30 kernel/sched/core.c:6954
__schedule_loop kernel/sched/core.c:7036 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7051
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7108
rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1088
__down_read_common kernel/locking/rwsem.c:1263 [inline]
__down_read kernel/locking/rwsem.c:1276 [inline]
down_read+0x98/0x2e0 kernel/locking/rwsem.c:1541
mmap_read_lock include/linux/mmap_lock.h:412 [inline]
exit_mm+0xcc/0x2c0 kernel/exit.c:557
do_exit+0x648/0x2300 kernel/exit.c:947
do_group_exit+0x21c/0x2d0 kernel/exit.c:1100
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
ret_from_fork+0x47f/0x770 arch/x86/kernel/process.c:157
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
2 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/31:
#0: ffffffff8e13d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13d8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5606:
#0: ffff88802fd9e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/6564:
#0: ffffffff8e143338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#0: ffffffff8e143338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:967
1 lock held by syz.4.162/6692:
#0: ffff88802779a220 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:356 [inline]
#0: ffff88802779a220 (&mm->mmap_lock){++++}-{4:4}, at: do_mbind mm/mempolicy.c:1460 [inline]
#0: ffff88802779a220 (&mm->mmap_lock){++++}-{4:4}, at: kernel_mbind mm/mempolicy.c:1682 [inline]
#0: ffff88802779a220 (&mm->mmap_lock){++++}-{4:4}, at: __do_sys_mbind mm/mempolicy.c:1756 [inline]
#0: ffff88802779a220 (&mm->mmap_lock){++++}-{4:4}, at: __se_sys_mbind+0x613/0xc30 mm/mempolicy.c:1752
1 lock held by syz.4.162/6716:
1 lock held by syz.4.162/6719:
#0: ffff88802779a220 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:412 [inline]
#0: ffff88802779a220 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557
3 locks held by syz.2.467/8434:
2 locks held by udevadm/8492:
1 lock held by udevadm/8493:
1 lock held by dhcpcd/8494:
#0: ffff888070064258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline]
#0: ffff888070064258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3251
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-next-20250718-syzkaller #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:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
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: 13 Comm: kworker/u8:1 Not tainted 6.16.0-rc6-next-20250718-syzkaller #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:hlock_class kernel/locking/lockdep.c:246 [inline]
RIP: 0010:__lock_acquire+0xa51/0xd20 kernel/locking/lockdep.c:5237
Code: 90 0f 0b 90 90 90 31 c0 48 8b 3c 24 48 83 78 40 00 0f 84 8c 02 00 00 41 8b 46 20 25 ff 1f 00 00 48 0f a3 05 91 12 0e 12 73 10 <48> 69 c0 c8 00 00 00 48 8d 80 30 83 4c 93 eb 40 83 3d f8 a1 11 18
RSP: 0018:ffffc90000127880 EFLAGS: 00000003
RAX: 0000000000000007 RBX: 0000000000000002 RCX: 0000000051d46eab
RDX: 00000000ac4ae0b4 RSI: 000000004c1d61f6 RDI: ffff88801ce98000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8b46212a
R10: dffffc0000000000 R11: fffffbfff1f454e7 R12: 000000008abd2c1b
R13: ffff88801ce98af0 R14: ffff88801ce98b40 R15: 0cdb2a4451d46eab
FS: 0000000000000000(0000) GS:ffff888125ce3000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a0a3588 CR3: 000000000df38000 CR4: 00000000003526f0
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_process_nc_paths+0xdb/0x3a0 net/batman-adv/network-coding.c:687
batadv_nc_worker+0x429/0x610 net/batman-adv/network-coding.c:728
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245