INFO: task syz.2.471:10856 blocked for more than 143 seconds.
Not tainted 6.16.0-rc2-syzkaller-00162-g41687a5c6f8b #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.471 state:D stack:25160 pid:10856 tgid:10855 ppid:9561 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084
__down_read_common kernel/locking/rwsem.c:1248 [inline]
__down_read kernel/locking/rwsem.c:1261 [inline]
down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526
__super_lock fs/super.c:59 [inline]
super_lock+0x2a9/0x3b0 fs/super.c:121
user_get_super+0xc8/0x120 fs/super.c:998
quotactl_block fs/quota/quota.c:890 [inline]
__do_sys_quotactl fs/quota/quota.c:955 [inline]
__se_sys_quotactl+0x4da/0x950 fs/quota/quota.c:917
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: 0033:0x7fd51818e929
RSP: 002b:00007fd518fec038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fd5183b5fa0 RCX: 00007fd51818e929
RDX: 0000000000000000 RSI: 0000200000000040 RDI: ffffffff80000801
RBP: 00007fd518210b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000180 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd5183b5fa0 R15: 00007ffc287cbce8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
5 locks held by kworker/u8:4/56:
#0: ffff88801b2fb948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b2fb948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc900014d7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900014d7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f4f1490 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:662
#3: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12630
#4: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#4: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
3 locks held by kworker/u8:5/61:
#0: ffff8880304b6148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff8880304b6148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000212fbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000212fbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4198
2 locks held by dhcpcd/5487:
#0: ffffffff8f4e2988 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5ee/0x790 net/socket.c:1273
#1: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:553
2 locks held by getty/5581:
#0: ffff888035d620a0 (&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/u8:8/6410:
#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: ffffc9000b357bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000b357bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
2 locks held by syz-executor/7777:
2 locks held by syz-executor/9317:
1 lock held by syz.2.471/10856:
#0: ffff88805302e0e0 (&type->s_umount_key#106){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88805302e0e0 (&type->s_umount_key#106){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
1 lock held by syz-executor/11982:
#0: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979
1 lock held by syz.8.569/12105:
#0: ffff888077f7c0e0 (&type->s_umount_key#106){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff888077f7c0e0 (&type->s_umount_key#106){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
7 locks held by syz-executor/12132:
#0: ffff888035f34428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
#0: ffff888035f34428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
#1: ffff888060a66888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
#2: ffff88802742fa58 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
#3: ffffffff8ed98d28 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:166
#4: ffff888069ab50e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#4: ffff888069ab50e8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004
#5: ffff888069ab6250 (&devlink->lock_key#44){+.+.}-{4:4}, at: nsim_drv_probe+0xc1/0xb70 drivers/net/netdevsim/dev.c:1537
#6: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#6: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2143
1 lock held by syz-executor/12140:
#0: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979
4 locks held by syz-executor/12215:
#0: ffff888035f34428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
#0: ffff888035f34428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
#1: ffff8880295f5088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
#2: ffff88802742fb48 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
#3: ffffffff8ed98d28 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
2 locks held by syz-executor/12224:
#0: ffffffff8fa1e670 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8fa1e670 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8fa1e670 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f4fe088 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f4fe088 (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-rc2-syzkaller-00162-g41687a5c6f8b #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+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 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: 56 Comm: kworker/u8:4 Not tainted 6.16.0-rc2-syzkaller-00162-g41687a5c6f8b #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: netns cleanup_net
RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4858 [inline]
RIP: 0010:__lock_acquire+0x39c/0xd20 kernel/locking/lockdep.c:5190
Code: 8d e8 38 ce e5 ff 90 0f 0b 90 90 90 31 c0 48 8b 3c 24 0f b6 98 c4 00 00 00 41 8b 46 20 25 ff 1f 00 00 48 0f a3 05 a4 4b 03 12 <73> 17 48 69 c0 c8 00 00 00 48 8d 88 30 83 42 93 84 db 75 54 e9 32
RSP: 0018:ffffc900014d65e8 EFLAGS: 00000003
RAX: 0000000000000007 RBX: 0000000000000003 RCX: 0000000000000007
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88801a56bc00
RBP: 0000000000000007 R08: 0000000000000000 R09: ffffffff81729af5
R10: ffffc900014d6898 R11: fffff5200029ad15 R12: 0000000000020000
R13: 0000000000000000 R14: ffff88801a56c7e0 R15: ffff88801a56c6f0
FS: 0000000000000000(0000) GS:ffff888125c83000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6455ae7d60 CR3: 0000000061e98000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548
__call_rcu_common kernel/rcu/tree.c:3090 [inline]
call_rcu+0x142/0x990 kernel/rcu/tree.c:3210
call_rcu_hurry include/linux/rcupdate.h:115 [inline]
fib6_info_release include/net/ip6_fib.h:344 [inline]
fib6_del_route net/ipv6/ip6_fib.c:2060 [inline]
fib6_del+0x111f/0x1550 net/ipv6/ip6_fib.c:2093
fib6_clean_node+0x29f/0x590 net/ipv6/ip6_fib.c:2255
fib6_walk_continue+0x678/0x910 net/ipv6/ip6_fib.c:2177
fib6_walk+0x149/0x290 net/ipv6/ip6_fib.c:2225
fib6_clean_tree net/ipv6/ip6_fib.c:2305 [inline]
__fib6_clean_all+0x234/0x380 net/ipv6/ip6_fib.c:2321
rt6_sync_down_dev net/ipv6/route.c:5004 [inline]
rt6_disable_ip+0x120/0x720 net/ipv6/route.c:5009
addrconf_ifdown+0x15d/0x1880 net/ipv6/addrconf.c:3857
addrconf_notify+0x1bc/0x1010 net/ipv6/addrconf.c:-1
notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2268 [inline]
call_netdevice_notifiers net/core/dev.c:2282 [inline]
dev_close_many+0x29c/0x410 net/core/dev.c:1785
unregister_netdevice_many_notify+0x834/0x2320 net/core/dev.c:12047
unregister_netdevice_many net/core/dev.c:12140 [inline]
default_device_exit_batch+0x819/0x890 net/core/dev.c:12644
ops_exit_list net/core/net_namespace.c:206 [inline]
ops_undo_list+0x525/0x990 net/core/net_namespace.c:253
cleanup_net+0x4c5/0x800 net/core/net_namespace.c:686
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+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245