INFO: task syz.1.3515:13332 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.3515 state:D stack:26248 pid:13332 tgid:13331 ppid:5632 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1821/0x5740 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7f7/0x1550 kernel/locking/mutex.c:820
nfsd_nl_rpc_status_get_dumpit+0xdc/0x1410 fs/nfsd/nfsctl.c:1494
genl_dumpit+0x10b/0x1b0 net/netlink/genetlink.c:1026
netlink_dump+0x702/0xe10 net/netlink/af_netlink.c:2330
__netlink_dump_start+0x5cb/0x7e0 net/netlink/af_netlink.c:2445
genl_family_rcv_msg_dumpit+0x213/0x310 net/netlink/genetlink.c:1075
genl_family_rcv_msg net/netlink/genetlink.c:1191 [inline]
genl_rcv_msg+0x5e8/0x7a0 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2555
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1899
sock_sendmsg_nosec net/socket.c:787 [inline]
__sock_sendmsg net/socket.c:802 [inline]
____sys_sendmsg+0x972/0x9f0 net/socket.c:2698
___sys_sendmsg+0x2a5/0x360 net/socket.c:2752
__sys_sendmsg net/socket.c:2784 [inline]
__do_sys_sendmsg net/socket.c:2789 [inline]
__se_sys_sendmsg net/socket.c:2787 [inline]
__x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3e32d9ce59
RSP: 002b:00007f3e30ff6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f3e33015fa0 RCX: 00007f3e32d9ce59
RDX: 0000000000004000 RSI: 0000200000000180 RDI: 0000000000000003
RBP: 00007f3e32e32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3e33016038 R14: 00007f3e33015fa0 R15: 00007fffe93b03d8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5388:
#0: ffff888036cf00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
2 locks held by syz.2.2085/10180:
#0: ffffffff8fe377c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec8b180 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x1670 fs/nfsd/nfsctl.c:1948
3 locks held by syz.1.3515/13332:
#0: ffffffff8fe377c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffff8880797226e8 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2409
#2: ffffffff8ec8b180 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_rpc_status_get_dumpit+0xdc/0x1410 fs/nfsd/nfsctl.c:1494
2 locks held by syz.4.6986/20810:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x389/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
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: 20810 Comm: syz.4.6986 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x17/0x90 kernel/kcov.c:314
Code: 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 15 18 65 72 11 65 8b 0d 39 65 72 11 <81> e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba ec 16 00 00
RSP: 0018:ffffc9000423f200 EFLAGS: 00000046
RAX: ffffffff8207d843 RBX: ffff88801e29c480 RCX: 0000000080000001
RDX: ffff8880293e8000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffea0001cf5b07 R09: 1ffffd400039eb60
R10: dffffc0000000000 R11: fffff9400039eb61 R12: dffffc0000000000
R13: ffff88802981b9c0 R14: ffffea0001cf5b00 R15: ffffea0001cf5b30
FS: 00007f23184266c0(0000) GS:ffff88812539e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7acdfea2f8 CR3: 000000004295e000 CR4: 00000000003526f0
Call Trace:
obj_cgroup_memcg include/linux/memcontrol.h:380 [inline]
folio_memcg+0xc3/0x1c0 include/linux/memcontrol.h:434
folio_matches_lruvec include/linux/memcontrol.h:1501 [inline]
folio_lruvec_relock_irqsave include/linux/memcontrol.h:1523 [inline]
__page_cache_release+0x18e/0xd60 mm/swap.c:77
folios_put_refs+0x775/0xb40 mm/swap.c:993
folio_batch_release include/linux/folio_batch.h:101 [inline]
shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149
shmem_fallocate+0xdb8/0xec0 mm/shmem.c:3772
vfs_fallocate+0x669/0x7e0 fs/open.c:338
ioctl_preallocate fs/ioctl.c:289 [inline]
file_ioctl+0x5bf/0x860 fs/ioctl.c:329
do_vfs_ioctl+0xc26/0x1530 fs/ioctl.c:576
__do_sys_ioctl fs/ioctl.c:595 [inline]
__se_sys_ioctl+0x82/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f231759ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2318426028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f2317815fa0 RCX: 00007f231759ce59
RDX: 0000200000000180 RSI: 0000000040305828 RDI: 0000000000000003
RBP: 00007f2317632d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2317816038 R14: 00007f2317815fa0 R15: 00007ffc59005a18