INFO: task syz.6.2525:15295 blocked for more than 143 seconds.
Not tainted 6.16.0-rc6-syzkaller-00002-g155a3c003e55 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.2525 state:D stack:28296 pid:15295 tgid:15294 ppid:8677 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6879
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:596
nfsd_umount+0x42/0xd0 fs/nfsd/nfsctl.c:1386
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9d71d8e929
RSP: 002b:00007f9d72c8f038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: fffffffffffffffe RBX: 00007f9d71fb5fa0 RCX: 00007f9d71d8e929
RDX: 0000200000000140 RSI: 0000200000000080 RDI: 00002000000000c0
RBP: 00007f9d71e10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000001810004 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f9d71fb5fa0 R15: 00007ffc35992fd8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5597:
#0: ffff88814c54e0a0 (&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
4 locks held by kworker/u8:30/8837:
#0: ffff8880b8639e18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
#1: ffff8880b8623f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987
#2: ffff888023ea8768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6062 [inline]
#2: ffff888023ea8768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xc4/0x460 net/wireless/core.c:421
#3: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#3: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#3: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: ieee80211_sta_active_ibss+0xc3/0x330 net/mac80211/ibss.c:635
2 locks held by syz.5.2378/14781:
#0: ffffffff8f571ab0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e41bcc8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12a/0x1650 fs/nfsd/nfsctl.c:1922
2 locks held by syz.6.2525/15295:
#0: ffff88806fb960e0 (&type->s_umount_key#93){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88806fb960e0 (&type->s_umount_key#93){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88806fb960e0 (&type->s_umount_key#93){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffffffff8e41bcc8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:596
3 locks held by kworker/u8:0/15628:
1 lock held by syz.8.3020/17021:
#0: ffff88806fb960e0 (&type->s_umount_key#93){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88806fb960e0 (&type->s_umount_key#93){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
4 locks held by syz.3.3039/17087:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-syzkaller-00002-g155a3c003e55 #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+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 17087 Comm: syz.3.3039 Not tainted 6.16.0-rc6-syzkaller-00002-g155a3c003e55 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__might_fault+0x6d/0x130 mm/memory.c:6969
Code: 00 00 00 45 8b 3f 31 ff 44 89 fe e8 dd 16 b6 ff 45 85 ff 74 15 e8 93 12 b6 ff 5b 41 5c 41 5d 41 5e 41 5f 5d e9 94 f3 60 09 cc <4c> 89 f7 89 ee e8 79 65 88 ff 48 81 c3 58 05 00 00 49 89 dd 49 c1
RSP: 0018:ffffc900041bfc08 EFLAGS: 00000246
RAX: ffffffff820a1fb3 RBX: ffff888027805a00 RCX: 0000000000000002
RDX: ffff888027805a00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000b71 R08: 0000000000000000 R09: ffffffff81cbe326
R10: ffffc900041bf940 R11: ffffffffa02019c8 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff8c913fe0 R15: 0000000000000000
FS: 00007ff0e13d56c0(0000) GS:ffff888125c4f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000348030 CR3: 0000000033c52000 CR4: 00000000003526f0
Call Trace:
do_recvmmsg+0x330/0x770 net/socket.c:2929
__sys_recvmmsg net/socket.c:2997 [inline]
__do_sys_recvmmsg net/socket.c:3020 [inline]
__se_sys_recvmmsg net/socket.c:3013 [inline]
__x64_sys_recvmmsg+0x190/0x240 net/socket.c:3013
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: 0033:0x7ff0e358e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff0e13d5038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007ff0e37b6080 RCX: 00007ff0e358e929
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007ff0e3610b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007ff0e37b6080 R15: 00007ffedcc53cc8