INFO: task syz.4.1400:11286 blocked for more than 143 seconds.
Not tainted 6.15.0-rc6-syzkaller-01204-gb8fa067c4a76 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.1400 state:D stack:23624 pid:11286 tgid:11285 ppid:5833 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746
nfsd_nl_rpc_status_get_dumpit+0xd9/0x1280 fs/nfsd/nfsctl.c:1516
genl_dumpit+0x108/0x1b0 net/netlink/genetlink.c:1027
netlink_dump+0x651/0xe70 net/netlink/af_netlink.c:2309
__netlink_dump_start+0x5cb/0x7e0 net/netlink/af_netlink.c:2424
genl_family_rcv_msg_dumpit+0x1e7/0x2c0 net/netlink/genetlink.c:1076
genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline]
genl_rcv_msg+0x5da/0x790 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x21c/0x490 net/netlink/af_netlink.c:2534
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg+0x219/0x270 net/socket.c:727
____sys_sendmsg+0x505/0x830 net/socket.c:2566
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620
__sys_sendmsg net/socket.c:2652 [inline]
__do_sys_sendmsg net/socket.c:2657 [inline]
__se_sys_sendmsg net/socket.c:2655 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe6a218e969
RSP: 002b:00007fe6a2f34038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fe6a23b5fa0 RCX: 00007fe6a218e969
RDX: 0000000004000810 RSI: 0000200000000180 RDI: 0000000000000008
RBP: 00007fe6a2210ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe6a23b5fa0 R15: 00007fff4eb3c718
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
2 locks held by getty/5591:
#0: ffff8880343920a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900033532f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by kworker/0:7/5893:
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9000493fc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000493fc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffff8880538bf240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490
#3: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#3: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#3: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
#3: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x2390 arch/x86/kernel/unwind_orc.c:479
3 locks held by kworker/u8:15/6505:
2 locks held by syz.0.1032/9866:
#0: ffffffff8f35dc30 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e2139e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12a/0x1650 fs/nfsd/nfsctl.c:1923
2 locks held by kworker/u8:25/10978:
#0: ffff888024a3b148 ((wq_completion)nbd-del){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888024a3b148 ((wq_completion)nbd-del){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9001f267c60 ((work_completion)(&nbd->remove_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9001f267c60 ((work_completion)(&nbd->remove_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
6 locks held by kworker/u8:38/10995:
3 locks held by syz.4.1400/11286:
#0: ffffffff8f35dc30 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffff888060a026d0 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2388
#2: ffffffff8e2139e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_rpc_status_get_dumpit+0xd9/0x1280 fs/nfsd/nfsctl.c:1516
3 locks held by kworker/1:23/12511:
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9000416fc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000416fc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffff88805623b240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490
2 locks held by kworker/1:24/12512:
2 locks held by syz.3.2262/14760:
#0: ffffffff8f35dc30 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e2139e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12a/0x1650 fs/nfsd/nfsctl.c:1923
1 lock held by syz-executor/14838:
#0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
1 lock held by syz-executor/14902:
#0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-01204-gb8fa067c4a76 #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:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 3 Comm: pool_workqueue_ Not tainted 6.15.0-rc6-syzkaller-01204-gb8fa067c4a76 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:_find_next_bit+0x89/0xe0 lib/find_bit.c:145
Code: 00 00 fc ff df 4d 23 3c 24 74 26 49 83 e6 c0 4d 89 f5 f3 49 0f bc c7 4c 01 e8 48 39 d8 48 0f 43 c3 5b 41 5c 41 5d 41 5e 41 5f <5d> c3 cc cc cc cc cc 4e 8d 24 ef 49 83 c4 08 49 c1 e5 06 4d 89 e6
RSP: 0018:ffffc90000087c50 EFLAGS: 00000087
RAX: 00000000000025c5 RBX: ffffffff932afce8 RCX: 00000000000025c5
RDX: 00000000000025c5 RSI: 0000000000100000 RDI: ffffffff95ffdc00
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff81ab2c28 R12: ffffffff960a1ee0
R13: 0000000000000b06 R14: 0000000000000000 R15: 00000000000025c5
FS: 0000000000000000(0000) GS:ffff8881260b6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd2f595df98 CR3: 000000000dd38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
find_next_bit include/linux/find.h:69 [inline]
zap_class+0x1f0/0x360 kernel/locking/lockdep.c:6253
__lockdep_free_key_range kernel/locking/lockdep.c:6405 [inline]
lockdep_unregister_key+0x1a6/0x310 kernel/locking/lockdep.c:6607
wq_unregister_lockdep kernel/workqueue.c:4816 [inline]
pwq_release_workfn+0x6d5/0x870 kernel/workqueue.c:5112
kthread_worker_fn+0x507/0xb60 kernel/kthread.c:1010
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245