INFO: task syz.0.5716:26969 blocked for more than 143 seconds.
Not tainted 6.15.0-syzkaller-03589-gfeacb1774bd5 #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.5716 state:D stack:26472 pid:26969 tgid:26968 ppid:17402 task_flags:0x400448 flags:0x00024002
Call Trace:
context_switch kernel/sched/core.c:5392 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
__schedule_loop kernel/sched/core.c:6859 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6874
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148
io_wq_exit_workers io_uring/io-wq.c:1317 [inline]
io_wq_put_and_exit+0x31b/0x690 io_uring/io-wq.c:1345
io_uring_clean_tctx+0x11f/0x1a0 io_uring/tctx.c:203
io_uring_cancel_generic+0x68f/0x730 io_uring/io_uring.c:3204
io_uring_files_cancel include/linux/io_uring.h:19 [inline]
do_exit+0x56a/0x2550 kernel/exit.c:915
do_group_exit+0x21c/0x2d0 kernel/exit.c:1108
get_signal+0x125e/0x1310 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: 0033:0x7fad16f8e969
RSP: 002b:00007fad17ea3038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: 0000000000000db4 RBX: 00007fad171b5fa0 RCX: 00007fad16f8e969
RDX: 0000000000000000 RSI: 0000000000000db4 RDI: 0000000000000006
RBP: 00007fad17010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fad171b5fa0 R15: 00007fad172dfa28
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by dhcpcd/5494:
#0: ffff88803ee406d0 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2388
#1: ffffffff8f505988 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f505988 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6823
2 locks held by getty/5589:
#0: ffff88814c8210a0 (&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/0:6/5898:
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000464fbc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000464fbc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f505988 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
3 locks held by kworker/u8:17/5956:
#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: ffffc900048f7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900048f7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f505988 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
6 locks held by kworker/1:11/8464:
#0: ffff888143a9d948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888143a9d948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000b1e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000b1e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff8881443d2198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#2: ffff8881443d2198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5859
#3: ffff88803d795198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#3: ffff88803d795198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004
#4: ffff88803d794160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#4: ffff88803d794160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004
#5: ffff88803d6b9c18 (&dev->ctrl_urb_lock){+.+.}-{4:4}, at: em28xx_write_regs_req+0x14d/0x3e0 drivers/media/usb/em28xx/em28xx-core.c:147
5 locks held by kworker/u8:1/24751:
#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: ffffc9000ae6fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000ae6fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f4f8e50 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x145/0xbd0 net/core/net_namespace.c:608
#3: ffffffff8f505988 (rtnl_mutex){+.+.}-{4:4}, at: cleanup_net+0x611/0xbd0 net/core/net_namespace.c:644
#4: ffffffff8e1427f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#4: ffffffff8e1427f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
2 locks held by iou-wrk-26969/26970:
2 locks held by syz-executor/28574:
#0: ffffffff8fa1ec78 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8fa1ec78 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8fa1ec78 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f505988 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f505988 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f505988 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064
1 lock held by syz.6.6048/28607:
#0: ffffffff8f505988 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline]
#0: ffffffff8f505988 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3390
1 lock held by syz.5.6055/28644:
#0: ffffffff8e1427f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e1427f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-03589-gfeacb1774bd5 #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:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 12788 Comm: kworker/u8:5 Not tainted 6.15.0-syzkaller-03589-gfeacb1774bd5 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: kvfree_rcu_reclaim kfree_rcu_work
RIP: 0010:filter_irq_stacks+0x86/0xa0 kernel/stacktrace.c:403
Code: 0f 92 c1 48 3d eb f6 60 8b 0f 93 c0 08 c8 74 11 48 ff c3 49 83 c7 08 49 39 dc 75 ae 44 89 e3 eb 06 ff c3 eb 02 31 db 89 d8 5b <41> 5c 41 5d 41 5e 41 5f e9 fd 5d b4 09 cc cc cc cc cc cc cc cc cc
RSP: 0018:ffffc900034075f0 EFLAGS: 00000246
RAX: 000000000000000b RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 000000000000000b RDI: ffffc90003407690
RBP: ffffc900034078c0 R08: 000000000000000f R09: ffffffff81724865
R10: ffffc90003407598 R11: ffffffff81ac98f0 R12: 000000000000000b
R13: dffffc0000000000 R14: ffffc90003407690 R15: ffffc900034076e8
FS: 0000000000000000(0000) GS:ffff888125d8c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000bdf000 CR3: 000000007f7f4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000097 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
stack_depot_save_flags+0x40/0x900 lib/stackdepot.c:610
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_save_track+0x4f/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2380 [inline]
slab_free_freelist_hook mm/slub.c:2409 [inline]
slab_free_bulk mm/slub.c:4666 [inline]
kmem_cache_free_bulk+0x2d1/0x520 mm/slub.c:5243
kfree_bulk include/linux/slab.h:794 [inline]
kvfree_rcu_bulk+0xe5/0x1e0 mm/slab_common.c:1516
kfree_rcu_work+0xed/0x170 mm/slab_common.c:1594
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/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