INFO: task syz.1.1120:10883 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1120 state:D stack:26472 pid:10883 tgid:10863 ppid:5840 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
__schedule_loop kernel/sched/core.c:6946 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6961
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7018
rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write_nested+0x1b5/0x200 kernel/locking/rwsem.c:1707
inode_lock_nested include/linux/fs.h:1072 [inline]
__start_dirop fs/namei.c:2833 [inline]
start_dirop fs/namei.c:2844 [inline]
filename_create+0x1fb/0x360 fs/namei.c:4848
do_mkdirat+0xca/0x4b0 fs/namei.c:5125
__do_sys_mkdirat fs/namei.c:5155 [inline]
__se_sys_mkdirat fs/namei.c:5153 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:5153
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f395158de97
RSP: 002b:00007f39523f1e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f39523f1ef0 RCX: 00007f395158de97
RDX: 00000000000001ff RSI: 0000200000000640 RDI: 00000000ffffff9c
RBP: 0000200000000080 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000080 R11: 0000000000000246 R12: 0000200000000640
R13: 00007f39523f1eb0 R14: 0000000000000000 R15: 00002000000022c0
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3d980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3d980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df3d980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:7/1147:
2 locks held by getty/5585:
#0: ffff888033afc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/1:4/5879:
5 locks held by kworker/1:7/5913:
#0: ffff88801f2f1148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x841/0x15e0 kernel/workqueue.c:3236
#1: ffffc90004b8fb80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x868/0x15e0 kernel/workqueue.c:3237
#2: ffff888144fcd198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#2: ffff888144fcd198 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4ef0 drivers/usb/core/hub.c:5899
#3: ffff88807b471198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#3: ffff88807b471198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006
#4: ffff888026356160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#4: ffff888026356160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006
4 locks held by udevd/6193:
#0: ffff88807782f1c8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe20 fs/seq_file.c:182
#1: ffff8880771cf488 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172
#2: ffff8880321c33c8 (kn->active#22){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880321c33c8 (kn->active#22){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173
#3: ffff888026354198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:919 [inline]
#3: ffff888026354198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
3 locks held by syz.1.1120/10864:
2 locks held by syz.1.1120/10883:
#0: ffff88801bf7a420 (sb_writers#17){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509
#1: ffff88804bd61970 (&type->i_mutex_dir_key#11/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline]
#1: ffff88804bd61970 (&type->i_mutex_dir_key#11/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2833 [inline]
#1: ffff88804bd61970 (&type->i_mutex_dir_key#11/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2844 [inline]
#1: ffff88804bd61970 (&type->i_mutex_dir_key#11/1){+.+.}-{4:4}, at: filename_create+0x1fb/0x360 fs/namei.c:4848
2 locks held by syz.6.1454/12943:
#0: ffffffff8f2daf08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f2daf08 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6964
#1: ffffffff8df43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8df43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
=============================================
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_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:160 [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:346 [inline]
watchdog+0xfb5/0x1000 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5816 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_preemption_disabled+0x40/0x120 lib/smp_processor_id.c:53
Code: 08 65 8b 05 06 72 1a 07 65 8b 0d fb 71 1a 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d db 71 1a 07 48 3b 4c 24 08 0f 85 cc 00 00 00 <48> 83 c4 10 5b 41 5e 41 5f 5d e9 81 d1 02 00 cc 48 c7 04 24 00 00
RSP: 0018:ffffc900041ff888 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000202 RCX: 1af51d11b84fef00
RDX: 0000000000000000 RSI: ffffffff8d7a3ef2 RDI: ffffffff8bbf81e0
RBP: ffffc900041ffa50 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200083ff10 R12: 1ffff9200083ff30
R13: ffffffff89ca22a4 R14: ffff888028801b60 R15: ffff888077845b80
FS: 0000555558511500(0000) GS:ffff888125eba000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f15241b6ad8 CR3: 0000000027b2c000 CR4: 00000000003526f0
Call Trace:
lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline]
lock_release+0xb3/0x3d0 kernel/locking/lockdep.c:5888
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:165 [inline]
_raw_spin_unlock_bh+0x1b/0x40 kernel/locking/spinlock.c:210
lock_sock include/net/sock.h:1693 [inline]
tcp_recvmsg+0x1f4/0x810 net/ipv4/tcp.c:2928
inet_recvmsg+0x147/0x250 net/ipv4/af_inet.c:906
sock_recvmsg_nosec net/socket.c:1082 [inline]
sock_recvmsg+0x1a8/0x270 net/socket.c:1104
sock_read_iter+0x231/0x2f0 net/socket.c:1174
new_sync_read fs/read_write.c:491 [inline]
vfs_read+0x55a/0xa30 fs/read_write.c:572
ksys_read+0x145/0x250 fs/read_write.c:715
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa076f8e11d
Code: a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb bd e8 a8 48 00 00 0f 1f 84 00 00 00 00 00 80 3d 41 d4 22 00 00 74 17 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 5b c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec
RSP: 002b:00007fff7cc41e18 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa076f8e11d
RDX: 0000000000000004 RSI: 00007fff7cc41e2c RDI: 0000000000000003
RBP: 0000000000000000 R08: 7fffffffffffffff R09: 3fffffffffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff7cc42240
R13: 0000000000000004 R14: 00007fff7cc41e2c R15: 00007fff7cc41ec0
IPVS: fo: UDP 224.0.0.2:0 - no destination available