INFO: task syz-executor:5823 blocked for more than 144 seconds.
Not tainted 6.16.0-rc4-syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21176 pid:5823 tgid:5823 ppid:1 task_flags:0x40054c flags:0x00004006
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
wb_wait_for_completion+0x15f/0x260 fs/fs-writeback.c:216
sync_inodes_sb+0x1bb/0xa10 fs/fs-writeback.c:2833
sync_filesystem+0x17a/0x230 fs/sync.c:64
generic_shutdown_super+0x6f/0x2c0 fs/super.c:622
kill_block_super+0x44/0x90 fs/super.c:1755
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417
task_work_run+0x1d4/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6b5/0x22e0 kernel/exit.c:964
do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f551a5c1293
RSP: 002b:00007ffe78c63bf8 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: fffffffffffffffb RBX: 000055557c3d2640 RCX: 00007f551a5c1293
RDX: 0000000000008000 RSI: 000055557c3d2640 RDI: 0000000000000006
RBP: 000055557c3d2614 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000293 R12: ffffffffffffffa8
R13: 0000000000000016 R14: 000055557c3d2610 R15: 00007ffe78c66fa0
Showing all locks held in the system:
2 locks held by kworker/0:0/9:
#0: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
#1: ffff8880b8623f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39a/0x6d0 kernel/sched/psi.c:987
1 lock held by khungtaskd/31:
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
4 locks held by kworker/u8:5/70:
#0: ffff88801b2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000211fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000211fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f502bd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:662
#3: ffffffff8f50f7c8 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1c/0x1d0 drivers/net/wireguard/device.c:417
5 locks held by kworker/1:2/2146:
#0: ffff88823be1a148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88823be1a148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90004ff7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90004ff7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff888145740198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#2: ffff888145740198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5863
#3: ffff8880566e7198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#3: ffff8880566e7198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004
#4: ffff888030e22160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#4: ffff888030e22160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004
4 locks held by kworker/u8:7/3117:
2 locks held by syslogd/5175:
#0: ffff8880b8739f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
#1: ffff8880b8723f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39a/0x6d0 kernel/sched/psi.c:987
1 lock held by dhcpcd/5488:
#0: ffffffff8f50f7c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f50f7c8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979
2 locks held by getty/5585:
#0: ffff8880312d00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/5823:
#0: ffff88803471c0e0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88803471c0e0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88803471c0e0 (&type->s_umount_key#74){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffff888024cb27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff888024cb27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
7 locks held by kworker/0:3/5838:
#0: ffff88823be1a148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88823be1a148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90003017bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003017bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff8880284c0198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#2: ffff8880284c0198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5863
#3: ffff88805b3e8198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#3: ffff88805b3e8198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x910 drivers/usb/core/hub.c:2307
#4: ffff88807c743160
(&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
(&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline]
(&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x7c0 drivers/base/dd.c:1292
#5: ffffffff8f50f7c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#5: ffffffff8f50f7c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2143
#6: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#6: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
4 locks held by udevd/6040:
#0:
ffff888026958c30 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:182
#1: ffff888032059088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x55/0x3c0 fs/kernfs/file.c:154
#2: ffff888032979d58 (&ep->lock){.-.-}-{3:3}, at: ep_poll_callback+0xd3/0xb10 fs/eventpoll.c:1347
#3: ffff888032979ca8 (&ep->wq){....}-{3:3}, at: __wake_up_common_lock+0x2f/0x1f0 kernel/sched/wait.c:105
3 locks held by kworker/1:7/6078:
#0: ffff88823be1a148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88823be1a148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000518fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000518fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff88814574a198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#2: ffff88814574a198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5863
1 lock held by segctord/6353:
1 lock held by syz.0.196/6797:
#0: ffff88803471c0e0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88803471c0e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
1 lock held by syz.7.520/8331:
#0: ffffffff8f50f7c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f50f7c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f50f7c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4054
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc4-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: 5175 Comm: syslogd Not tainted 6.16.0-rc4-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__unix_dgram_recvmsg+0x4b7/0xde0 net/unix/af_unix.c:2545
Code: 07 00 00 ba 04 03 00 00 be 01 00 00 00 e8 f1 98 86 f7 eb 05 e8 1a 78 ab f7 48 8b 7c 24 20 49 89 ff 49 c1 ef 03 43 80 3c 2f 00 <74> 0a e8 d2 fa 0e f8 48 8b 7c 24 20 48 83 3f 00 0f 84 b2 00 00 00
RSP: 0018:ffffc9000419f980 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffff888034a73080 RCX: 0000000000000000
RDX: 0000000000000006 RSI: ffffffff8d98202e RDI: ffffc9000419fba0
RBP: ffffc9000419fb08 R08: ffffffff8fa104f7 R09: 1ffffffff1f4209e
R10: dffffc0000000000 R11: fffffbfff1f4209f R12: ffff88807dff3280
R13: dffffc0000000000 R14: ffff888034a72a28 R15: 1ffff92000833f74
FS: 00007fe4058cac80(0000) GS:ffff888125c50000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe079b2de9c CR3: 00000000274c3000 CR4: 0000000000350ef0
Call Trace:
sock_recvmsg_nosec net/socket.c:1017 [inline]
sock_recvmsg+0x22c/0x270 net/socket.c:1039
sock_read_iter+0x231/0x2f0 net/socket.c:1109
new_sync_read fs/read_write.c:491 [inline]
vfs_read+0x4d0/0x980 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/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe405a1a407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffd7a9bc880 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fe4058cac80 RCX: 00007fe405a1a407
RDX: 00000000000000ff RSI: 00005626a85d0950 RDI: 0000000000000000
RBP: 00005626a85d0910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005626a85d099c
R13: 0000000000000000 R14: 00005626a85d0950 R15: 0000562693f4bd98