INFO: task syz.3.2209:15058 blocked for more than 144 seconds.
Not tainted 6.15.0-rc7-next-20250522-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.2209 state:D stack:25960 pid:15058 tgid:15057 ppid:5837 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
netfs_wait_for_request+0x1f0/0x600 fs/netfs/misc.c:450
netfs_unbuffered_write_iter_locked+0x52a/0x910 fs/netfs/direct_write.c:110
netfs_unbuffered_write_iter+0x4c4/0x660 fs/netfs/direct_write.c:193
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x548/0xa90 fs/read_write.c:686
ksys_write+0x145/0x250 fs/read_write.c:738
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: 0033:0x7ff6c5d8e969
RSP: 002b:00007ff6c6c78038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ff6c5fb5fa0 RCX: 00007ff6c5d8e969
RDX: 0000000000020000 RSI: 0000200000000180 RDI: 0000000000000006
RBP: 00007ff6c5e10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff6c5fb5fa0 R15: 00007ffcd9ee37e8
Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/31:
#0: ffffffff8e13f140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13f140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5599:
#0: ffff888030cd30a0 (&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/u8:10/5986:
#0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc900050a7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900050a7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f511d48 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
3 locks held by syz.3.2209/15058:
#0: ffff888079b13438 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1213
#1: ffff88807bae6428 (sb_writers#14){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3092 [inline]
#1: ffff88807bae6428 (sb_writers#14){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
#2: ffff888059ab9b08 (&sb->s_type->i_mutex_key#23){++++}-{4:4}, at: netfs_start_io_direct+0x1ef/0x230 fs/netfs/locking.c:188
5 locks held by kworker/u8:14/15968:
#0: ffff88801b2fe148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b2fe148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90003b47bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003b47bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f505190 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x8a0 net/core/net_namespace.c:662
#3: ffffffff8f511d48 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12622
#4: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#4: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
2 locks held by syz-executor/16243:
#0: ffffffff8fa30b58 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8fa30b58 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8fa30b58 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f511d48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f511d48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f511d48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4065
1 lock held by syz.6.2531/16350:
#0: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
1 lock held by syz.6.2531/16354:
#0: ffffffff8f511d48 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x37a/0x1d90 drivers/net/tun.c:3038
1 lock held by syz.6.2531/16355:
#0: ffffffff8f511d48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f511d48 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x323/0x1b50 net/ipv4/devinet.c:1121
1 lock held by syz.1.2532/16361:
#0: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3782
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc7-next-20250522-syzkaller #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: 5823 Comm: syz-executor Not tainted 6.15.0-rc7-next-20250522-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:_raw_spin_lock_irqsave+0xc3/0xf0 kernel/locking/spinlock.c:162
Code: 00 00 00 45 31 c9 ff 75 08 e8 99 86 37 f6 48 83 c4 08 48 89 df e8 ed 2a 38 f6 48 c7 04 24 0e 36 e0 45 4b c7 04 27 00 00 00 00 <65> 48 8b 05 e5 d5 35 07 48 3b 44 24 48 75 15 4c 89 f0 48 8d 65 e0
RSP: 0018:ffffc90004257aa0 EFLAGS: 00000046
RAX: 5e2e438a22149200 RBX: ffff8880b8627ac0 RCX: dffffc0000000000
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90004257a20
RBP: ffffc90004257b38 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200084af44 R12: dffffc0000000000
R13: ffffc90004257d40 R14: 0000000000000a02 R15: 1ffff9200084af54
FS: 0000555560d47500(0000) GS:ffff888125c59000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fecd2f7ed38 CR3: 0000000078202000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_hrtimer_base kernel/time/hrtimer.c:171 [inline]
hrtimer_start_range_ns+0xd1/0x1080 kernel/time/hrtimer.c:1327
hrtimer_start_expires include/linux/hrtimer.h:277 [inline]
hrtimer_sleeper_start_expires kernel/time/hrtimer.c:2023 [inline]
do_nanosleep+0x191/0x600 kernel/time/hrtimer.c:2097
hrtimer_nanosleep+0x169/0x360 kernel/time/hrtimer.c:2147
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1399 [inline]
__se_sys_clock_nanosleep+0x2f1/0x380 kernel/time/posix-timers.c:1376
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: 0033:0x7f1bc3fc11e3
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:00007ffee4544eb8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1bc3fc11e3
RDX: 00007ffee4544ed0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 00000000144d882e R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffee4545320
R13: 0000000000000004 R14: 00007ffee4544f0c R15: 00007ffee4544fa0