INFO: task syz.3.1163:14839 blocked for more than 143 seconds.
Not tainted 6.15.0-rc4-syzkaller-00051-g7a13c14ee59d #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1163 state:D stack:28952 pid:14839 tgid:14831 ppid:12697 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
percpu_rwsem_wait+0x2ab/0x300 kernel/locking/percpu-rwsem.c:162
__percpu_down_read+0xe3/0x120 kernel/locking/percpu-rwsem.c:177
percpu_down_read include/linux/percpu-rwsem.h:66 [inline]
__sb_start_write include/linux/fs.h:1783 [inline]
sb_start_write+0x185/0x1c0 include/linux/fs.h:1919
mnt_want_write+0x41/0x90 fs/namespace.c:556
filename_create+0x13a/0x470 fs/namei.c:4125
do_mkdirat+0xa0/0x590 fs/namei.c:4384
__do_sys_mkdirat fs/namei.c:4409 [inline]
__se_sys_mkdirat fs/namei.c:4407 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4407
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbce1f8d1d7
RSP: 002b:00007fbce2e86e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fbce2e86ef0 RCX: 00007fbce1f8d1d7
RDX: 00000000000001ff RSI: 0000200000000000 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000200000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000000
R13: 00007fbce2e86eb0 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
3 locks held by kworker/u8:0/12:
#0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90000117c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000117c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2e2008 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by khungtaskd/31:
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
2 locks held by kworker/u8:3/53:
5 locks held by kworker/u8:4/63:
#0: ffff88801aef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801aef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9000155fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000155fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2d54d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x145/0xbd0 net/core/net_namespace.c:608
#3: ffffffff8f2e2008 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12524
#4: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#4: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
5 locks held by kworker/u8:10/3526:
1 lock held by dhcpcd/5486:
#0: ffffffff8f2e2008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f2e2008 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x323/0x1b50 net/ipv4/devinet.c:1121
2 locks held by getty/5574:
#0: ffff8880342290a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz.3.1163/14839:
#0: ffff888063100420 (sb_writers#29){++++}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
7 locks held by syz-executor/16848:
#0: ffff8880345aa420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline]
#0: ffff8880345aa420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:680
#1: ffff88806915bc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
#2: ffff888026800e18 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
#3: ffffffff8eb82128 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
#4: ffff8880275470e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#4: ffff8880275470e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline]
#4: ffff8880275470e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x7c0 drivers/base/dd.c:1292
#5: ffff888027543250 (&devlink->lock_key#31){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675
#6: ffffffff8f2e2008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#6: ffffffff8f2e2008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2089
1 lock held by syz-executor/16927:
#0: ffffffff8f2e2008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f2e2008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f2e2008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064
2 locks held by syz.8.1482/17139:
2 locks held by syz.6.1481/17140:
2 locks held by syz.4.1478/17143:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller-00051-g7a13c14ee59d #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
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:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
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: 5804 Comm: syz-executor Not tainted 6.15.0-rc4-syzkaller-00051-g7a13c14ee59d #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:102 [inline]
RIP: 0010:do_raw_spin_unlock+0x7b/0x240 kernel/locking/spinlock_debug.c:141
Code: c1 e8 03 42 0f b6 04 20 84 c0 0f 85 74 01 00 00 83 3b 00 0f 84 ea 00 00 00 4c 8d 73 10 4d 89 f5 49 c1 ed 03 43 80 7c 25 00 00 <74> 08 4c 89 f7 e8 7b d9 80 00 65 48 8b 04 25 08 00 72 92 49 39 06
RSP: 0018:ffffc9000405f910 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff8880b88399c0 RCX: ffffffff819eb50d
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b88399c0
RBP: ffffc9000405f9b0 R08: ffff8880b88399c3 R09: 1ffff11017107338
R10: dffffc0000000000 R11: ffffed1017107339 R12: dffffc0000000000
R13: 1ffff1101710733a R14: ffff8880b88399d0 R15: ffff8880b883a558
FS: 00005555691c3500(0000) GS:ffff888126100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055729d7120e0 CR3: 0000000033002000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_unlock+0x1e/0x50 kernel/locking/spinlock.c:186
raw_spin_rq_unlock kernel/sched/core.c:649 [inline]
raw_spin_rq_unlock_irq kernel/sched/sched.h:1524 [inline]
finish_lock_switch kernel/sched/core.c:5130 [inline]
finish_task_switch+0x261/0x950 kernel/sched/core.c:5248
context_switch kernel/sched/core.c:5385 [inline]
__schedule+0x1697/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
do_nanosleep+0x1c7/0x600 kernel/time/hrtimer.c:2100
hrtimer_nanosleep+0x169/0x360 kernel/time/hrtimer.c:2147
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1407 [inline]
__se_sys_clock_nanosleep+0x2ee/0x380 kernel/time/posix-timers.c:1384
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f64443c11e3
Code: 1f 84 00 00 00 00 00 83 ff 03 74 7b 83 ff 02 b8 fa ff ff ff 49 89 ca 0f 44 f8 80 3d 5e 33 1c 00 00 74 14 b8 e6 00 00 00 0f 05 d8 c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec 28 48 89 54 24 10
RSP: 002b:00007ffcf32b8d78 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f64443c11e3
RDX: 00007ffcf32b8d90 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 000000000e436b87 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffcf32b91e0
R13: 0000000000000004 R14: 00007ffcf32b8dcc R15: 00007ffcf32b8e60