INFO: task syz.3.1582:12100 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1582 state:D stack:27672 pid:12100 tgid:12099 ppid:5828 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x818/0x1060 kernel/locking/mutex.c:760
nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1880
genl_family_rcv_msg_doit+0x209/0x2f0 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2552
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa98/0xc70 net/socket.c:2630
___sys_sendmsg+0x134/0x1d0 net/socket.c:2684
__sys_sendmsg+0x16d/0x220 net/socket.c:2716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdbaa98f6c9
RSP: 002b:00007fdbab913038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fdbaabe5fa0 RCX: 00007fdbaa98f6c9
RDX: 0000000000044000 RSI: 0000200000000f00 RDI: 0000000000000003
RBP: 00007fdbaaa11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdbaabe6038 R14: 00007fdbaabe5fa0 R15: 00007fffbff7b708
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3c45a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c45a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c45a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/8839:
#0: ffff88814de380a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900173132f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
2 locks held by syz.1.1569/12056:
#0: ffffffff9018e850 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7ed208 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1880
2 locks held by syz.3.1582/12100:
#0: ffffffff9018e850 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7ed208 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1880
2 locks held by syz.5.1680/12550:
#0: ffffffff9018e850 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7ed208 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1880
2 locks held by syz.0.1713/12704:
#0: ffffffff9018e850 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7ed208 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1880
1 lock held by syz.4.1977/13853:
#0: ffff88808355ebc8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x117/0x530 mm/mmap_lock.c:238
1 lock held by syz.4.1977/13857:
#0: ffff88805c367a88 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x117/0x530 mm/mmap_lock.c:238
1 lock held by syz.6.2028/14031:
#0: ffffffff8e3cfa00 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3820
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf3f/0x1170 kernel/hung_task.c:495
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
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: 5200 Comm: udevd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:min_vruntime_update kernel/sched/fair.c:832 [inline]
RIP: 0010:min_vruntime_cb_propagate kernel/sched/fair.c:842 [inline]
RIP: 0010:rb_add_augmented_cached include/linux/rbtree_augmented.h:83 [inline]
RIP: 0010:__enqueue_entity+0x330/0xb70 kernel/sched/fair.c:853
Code: 20 41 80 3c 2a 00 0f 85 9d 03 00 00 48 8d 7b 10 4c 8b 6b 08 49 89 fa 49 c1 ea 03 41 80 3c 2a 00 0f 85 3e 03 00 00 48 8d 7b 70 <4c> 8b 73 10 49 89 fa 49 c1 ea 03 41 80 3c 2a 00 0f 85 ae 03 00 00
RSP: 0018:ffffc90003037a48 EFLAGS: 00000046
RAX: 000000364c4a09e7 RBX: ffff888031f25b50 RCX: ffff88807e8dbd10
RDX: ffff8880b843a580 RSI: ffff8880b843a5c8 RDI: ffff888031f25bc0
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000155cc0
R10: 1ffff110063e4b6c R11: 0000000000000001 R12: 000000364c4a09e7
R13: ffff88807e8dbd10 R14: 000000364cfc77e3 R15: ffff88807e8dbc80
FS: 00007fd763d8d880(0000) GS:ffff888124a0d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000003a95000 CR3: 000000007e188000 CR4: 00000000003526f0
Call Trace:
put_prev_entity+0x15d/0x290 kernel/sched/fair.c:5553
put_prev_task_fair+0x3c/0x80 kernel/sched/fair.c:8984
put_prev_set_next_task kernel/sched/sched.h:2503 [inline]
pick_next_task kernel/sched/core.c:6264 [inline]
__schedule+0x1655/0x5de0 kernel/sched/core.c:6870
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7113
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
__dentry_kill+0x521/0x600 fs/dcache.c:690
dput.part.0+0x4b1/0x9b0 fs/dcache.c:911
dput+0x1f/0x30 fs/dcache.c:901
lookup_one_qstr_excl+0x201/0x250 fs/namei.c:1714
do_unlinkat+0x284/0x6a0 fs/namei.c:4725
__do_sys_unlink fs/namei.c:4783 [inline]
__se_sys_unlink fs/namei.c:4781 [inline]
__x64_sys_unlink+0xc5/0x110 fs/namei.c:4781
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd763715937
Code: 00 00 e9 a9 fd ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 5f 00 00 00 0f 05 c3 0f 1f 84 00 00 00 00 00 b8 57 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 91 b4 0d 00 f7 d8 64 89 02 b8
RSP: 002b:00007ffcd296e2b8 EFLAGS: 00000202 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000bb8 RCX: 00007fd763715937
RDX: 0000000000000000 RSI: 000000002512f780 RDI: 000055c4638fa02e
RBP: 0000000000000000 R08: 00000000251a4732 R09: 00007fd763eb7000
R10: 0000000000000001 R11: 0000000000000202 R12: 0000000000000000
R13: 000055c463915100 R14: 0000000000000001 R15: 0000000000000000