INFO: task syz.1.3471:19878 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.3471 state:D stack:26432 pid:19878 tgid:19878 ppid:18602 task_flags:0x40044c flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
__schedule_loop kernel/sched/core.c:6948 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6963
wb_wait_for_completion+0x360/0x680 fs/fs-writeback.c:226
sync_inodes_sb+0x1c9/0xb40 fs/fs-writeback.c:2894
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:1722
ext4_kill_sb+0x68/0xb0 fs/ext4/super.c:7444
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318
task_work_run+0x1d4/0x260 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6c5/0x2310 kernel/exit.c:971
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: eccb:0xe4a421182f13d611
RSP: 002b:00007f8aab498f80 EFLAGS: 00000756 ORIG_RAX: d1d66dbfed01019b
RAX: 2bf9e1987c4f44ee RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 532828f82bbb556c R08: dbce39d105fdbf88 R09: ae9ea378b9c9fbc7
R10: 33740f3b8630618c R11: 2450ade207355af5 R12: 0a61688f027fb1a4
R13: 339c71c774e61334 R14: 28baed4a0483d193 R15: 7c1f9cf2b758efdc
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13f8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e13f8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5581:
#0: ffff88814dfca0a0 (&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+0x449/0x1460 drivers/tty/n_tty.c:2211
4 locks held by kworker/u8:13/6036:
3 locks held by kworker/u8:51/12548:
#0: ffff88813fe29948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
#1: ffffc90004defb80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
#2: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
5 locks held by kworker/u8:2/17042:
#0: ffff88801ba9f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
#1: ffffc90002eb7b80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
#2: ffffffff8f5034d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7a0 net/core/net_namespace.c:670
#3: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x9e0 net/core/dev.c:13041
#4: ffffffff8e1453f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#4: ffffffff8e1453f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:956
2 locks held by syz.1.3471/19878:
#0: ffff8880554240e0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff8880554240e0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff8880554240e0 (&type->s_umount_key#32){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffff888141f6e820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline]
#1: ffff888141f6e820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40 fs/fs-writeback.c:2892
1 lock held by syz.6.4190/21927:
#0: ffff8880554240e0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff8880554240e0 (&type->s_umount_key#32){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
2 locks held by syz-executor/22571:
#0: ffffffff8eca1208 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8eca1208 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8eca1208 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
4 locks held by syz.4.4402/22633:
1 lock held by syz.5.4404/22660:
#0: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6964
1 lock held by syz.5.4404/22661:
#0: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6964
1 lock held by syz.5.4404/22662:
#0: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f510b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6964
2 locks held by syz.7.4407/22669:
#0: ffff888077e0fac8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff888077e0fac8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x89/0x250 net/socket.c:665
#1: ffffffff8e1453f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e1453f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:956
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
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:363 [inline]
watchdog+0xe40/0xe90 kernel/hung_task.c:557
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: 20170 Comm: kworker/u8:1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: gid-cache-wq netdevice_event_work_handler
RIP: 0010:detach_timer+0x160/0x2c0 kernel/time/timer.c:892
Code: 74 2a e8 63 06 13 00 41 80 3c 2e 00 74 08 4c 89 ef e8 14 63 79 00 49 c7 45 00 00 00 00 00 eb 11 e8 45 06 13 00 80 7c 24 04 00 <75> d6 e8 39 06 13 00 80 3c 2b 00 48 8b 5c 24 08 74 08 48 89 df e8
RSP: 0018:ffffc90000007c58 EFLAGS: 00000002
RAX: ffffffff81aec33b RBX: 1ffff11005ff6202 RCX: ffff88802d710000
RDX: 0000000000000100 RSI: ffffffff8be075c0 RDI: ffffffff8be07580
RBP: dffffc0000000000 R08: ffffffff8fa20e77 R09: 1ffffffff1f441ce
R10: dffffc0000000000 R11: fffffbfff1f441cf R12: ffffc90000007d60
R13: ffff88802ffb1018 R14: 1ffff11005ff6203 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125c2d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31016ff8 CR3: 0000000076b7c000 CR4: 00000000003526f0
Call Trace:
expire_timers kernel/time/timer.c:1782 [inline]
__run_timers kernel/time/timer.c:2373 [inline]
__run_timer_base+0x59b/0x860 kernel/time/timer.c:2385
run_timer_base kernel/time/timer.c:2394 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2404
handle_softirqs+0x27d/0x850 kernel/softirq.c:626
__do_softirq kernel/softirq.c:660 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:727
irq_exit_rcu+0x9/0x30 kernel/softirq.c:743
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:console_flush_one_record arch/x86/include/asm/irqflags.h:-1 [inline]
RIP: 0010:console_flush_all+0x846/0xb60 kernel/printk/printk.c:3289
Code: ff ff e8 bd 41 20 00 90 0f 0b 90 e9 53 fc ff ff e8 af 41 20 00 e8 3a 7a bb 09 48 85 db 74 c0 e8 a0 41 20 00 fb 48 8b 5c 24 10 <48> 8b 44 24 20 42 80 3c 20 00 4c 8b 74 24 18 74 08 4c 89 f7 e8 51
RSP: 0018:ffffc9000407f460 EFLAGS: 00000293
RAX: ffffffff81a187e0 RBX: ffffc9000407f600 RCX: ffff88802d710000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000407f5b0 R08: ffffffff8fa20e77 R09: 1ffffffff1f441ce
R10: dffffc0000000000 R11: fffffbfff1f441cf R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000000 R15: ffffffff8e98f620
__console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
vprintk_emit+0x4f8/0x5f0 kernel/printk/printk.c:2426
_printk+0xcf/0x120 kernel/printk/printk.c:2451
del_netdev_ips0+0x2c/0x60 drivers/infiniband/core/roce_gid_mgmt.c:445
ib_enum_roce_netdev+0x1ab/0x2e0 drivers/infiniband/core/device.c:2452
ib_enum_all_roce_netdevs+0xcc/0x160 drivers/infiniband/core/device.c:2478
netdevice_event_work_handler+0xef/0x260 drivers/infiniband/core/roce_gid_mgmt.c:660
process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443
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