INFO: task syz.1.340:7212 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.340 state:D stack:27016 pid:7212 tgid:7210 ppid:5601 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x1259/0x6920 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7376
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7433
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xccb/0x1bd0 kernel/locking/mutex.c:821
nfsd_nl_expkey_set_reqs_doit+0x8a/0x2f0 fs/nfsd/export.c:561
genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2575
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline]
netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1364
netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1919
sock_sendmsg_nosec net/socket.c:800 [inline]
__sock_sendmsg net/socket.c:815 [inline]
____sys_sendmsg+0xa4d/0xbe0 net/socket.c:2713
___sys_sendmsg+0x190/0x1e0 net/socket.c:2767
__sys_sendmsg+0x160/0x210 net/socket.c:2799
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd39d99e159
RSP: 002b:00007fd39e87a028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd39dc26090 RCX: 00007fd39d99e159
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000007
RBP: 00007fd39da3506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd39dc26128 R14: 00007fd39dc26090 R15: 00007ffc0fe62f88
Showing all locks held in the system:
locks held by kworker/u8:1/13: 2, last CPU#0:
#0: ffff88801c094140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90000127d08 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by pr/ttyS0/16: 1, last CPU#0:
#0: ffffffff8edd88b8 (console_srcu
){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline]
){....}-{0:0}, at: console_srcu_read_lock+0x49/0x60 kernel/printk/printk.c:291
locks held by khungtaskd/32: 1, last CPU#0:
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6871
locks held by kworker/u8:3/50: 1, last CPU#0:
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: process_one_work+0x880/0x1b10 kernel/workqueue.c:3361
locks held by kworker/u8:4/59: 3, last CPU#0:
#0: ffff88801c094140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc9000201fd08 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffff8880756bc258 (&devlink->lock_key#10){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x56/0xd20 drivers/net/netdevsim/dev.c:834
#2: ffff8880756bc258 (&devlink->lock_key#10){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x56/0xd20 drivers/net/netdevsim/dev.c:834
locks held by kworker/u8:5/68: 3, last CPU#0:
#0: ffff88801c094140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffff8880b8424568 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:218 [inline]
#1: ffff8880b8424568 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2e0c/0x6920 kernel/sched/core.c:7278
#2: ffff888092360800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6905 [inline]
#2: ffff888092360800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0x92/0x550 net/wireless/core.c:550
locks held by kworker/u8:7/152: 3, last CPU#0:
#0: ffff88801c094140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90002ecfd08 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffff88807e614258 (&devlink->lock_key#6){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x56/0xd20 drivers/net/netdevsim/dev.c:834
locks held by getty/5363: 2, on CPU#0:
#0: ffff8880382dd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900032262e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
locks held by syz-executor/5588: 2, last CPU#0:
#0: ffff88802c915900 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline]
#0: ffff88802c915900 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x124/0xa00 mm/mmap.c:1299
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
locks held by kworker/1:4/5699: 2, last CPU#1:
#0: ffff8880585fe940 ((wq_completion)wg-crypt-wg2#11){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc900045afd08 ((work_completion)(&peer->transmit_packet_work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by syz.3.148/6352: 2, on CPU#0:
#0: ffffffff90d84248 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8f2899c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x1a3/0x1dc0 fs/nfsd/nfsctl.c:2057
locks held by syz.1.340/7212: 2, on CPU#0:
#0: ffffffff90d84248 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8f2899c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_expkey_set_reqs_doit+0x8a/0x2f0 fs/nfsd/export.c:561
locks held by syz-executor/7910: 4, last CPU#0:
#0: ffffffff8ef3deb0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1542 [inline]
#0: ffffffff8ef3deb0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm kernel/fork.c:1595 [inline]
#0: ffffffff8ef3deb0 (dup_mmap_sem){++++}-{0:0}, at: copy_process+0x4816/0x8380 kernel/fork.c:2311
#1: ffff8880375aa800 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#1: ffff8880375aa800 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x127/0x2370 mm/mmap.c:1716
#2: ffff8880269fc080 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline]
#2: ffff8880269fc080 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x1c9/0x2370 mm/mmap.c:1723
#3: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#3: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#3: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: page_table_check_set+0x11d/0x580 mm/page_table_check.c:112
locks held by syz.4.650/8845: 2, on CPU#0:
#0: ffffffff90d84248 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8f2899c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_expkey_set_reqs_doit+0x8a/0x2f0 fs/nfsd/export.c:561
locks held by syz.9.654/8880: 1, last CPU#1:
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
locks held by syz-executor/8988: 3, last CPU#1:
#0: ffffffff90052b68 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:198 [inline]
#0: ffffffff90052b68 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:305 [inline]
#0: ffffffff90052b68 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x113/0x2c0 net/core/rtnetlink.c:599
#1: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
#1: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xac3/0x2620 net/core/rtnetlink.c:4219
#2: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#2: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#2: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#2: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
locks held by syz.3.683/9032: 1, on CPU#1:
#0: ffffffff8edf8378 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6d0 kernel/rcu/tree.c:3904
locks held by syz.8.693/9031: 2, last CPU#0:
#0: ffff8880269f8340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline]
#0: ffff8880269f8340 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x124/0xa00 mm/mmap.c:1299
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x310 mm/pgtable-generic.c:290
locks held by syz.6.695/9051: 2, on CPU#0:
#0: ffffffff8ffeb720 (ubi_devices_mutex){+.+.}-{4:4}, at: ctrl_cdev_ioctl+0x327/0x410 drivers/mtd/ubi/cdev.c:1112
#1: ffffffff8edf8378 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6d0 kernel/rcu/tree.c:3904
locks held by vhost-9051/9053: 3, on CPU#1:
#0: ffff8880794138e0 (&vtsk->exit_mutex){+.+.}-{4:4}, at: vhost_task_fn+0x2bc/0x430 kernel/vhost_task.c:54
#1: ffff888058c5f678 (&worker->mutex){+.+.}-{4:4}, at: vhost_worker_killed+0x55/0x3d0 drivers/vhost/vhost.c:482
#2: ffffffff8edf84a8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
locks held by syz.9.696/9055: 2, last CPU#1:
#0: ffff88807df78308 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x21f/0x2a0 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 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: 16 Comm: pr/ttyS0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:410
Code: a3 5a fc 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c e9 bd 15 24 06 e8 88 0d ce fc eb a2 e8 11 0e
RSP: 0018:ffffc90000157958 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff85b1a170 RDI: ffffffff9bc75f60
RBP: ffffffff9bc75f20 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 205d323354202020 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff378ec41 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888123b4f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2ffe557e20 CR3: 00000000759d1000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x13a/0x210 drivers/tty/serial/8250/8250_port.c:2013
serial8250_fifo_wait_for_lsr_thre+0x5f/0xd0 drivers/tty/serial/8250/8250_port.c:3270
__serial8250_console_fifo_write+0xa5/0x290 drivers/tty/serial/8250/8250_port.c:3345
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline]
__serial8250_console_write drivers/tty/serial/8250/8250_port.c:3429 [inline]
serial8250_console_write+0xf46/0x1330 drivers/tty/serial/8250/8250_port.c:3493
nbcon_emit_next_record+0x8f7/0xa70 kernel/printk/nbcon.c:1070
nbcon_emit_one+0x1a8/0x2b0 kernel/printk/nbcon.c:1157
nbcon_kthread_func+0x613/0x7d0 kernel/printk/nbcon.c:1271
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245