INFO: task syz.4.47:6223 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.47 state:D stack:28104 pid:6223 tgid:6220 ppid:5793 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x145f/0x5070 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
percpu_rwsem_wait+0x2e6/0x330 kernel/locking/percpu-rwsem.c:164
__percpu_down_read+0xfc/0x140 kernel/locking/percpu-rwsem.c:180
percpu_down_read_internal include/linux/percpu-rwsem.h:67 [inline]
percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
__sb_start_write include/linux/fs/super.h:19 [inline]
sb_start_write include/linux/fs/super.h:125 [inline]
quotactl_block fs/quota/quota.c:899 [inline]
__do_sys_quotactl fs/quota/quota.c:955 [inline]
__se_sys_quotactl+0x83c/0x950 fs/quota/quota.c:917
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2b9671f749
RSP: 002b:00007f2b94944038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f2b96976180 RCX: 00007f2b9671f749
RDX: 0000000000000000 RSI: 00002000000000c0 RDI: ffffffff80000801
RBP: 00007f2b967a3f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000380 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2b96976218 R14: 00007f2b96976180 R15: 00007fffdb3978f8
Showing all locks held in the system:
5 locks held by kworker/u8:2/37:
1 lock held by khungtaskd/39:
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:7/993:
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc900047efbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc900047efbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8e898760 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7b0 net/core/net_namespace.c:670
#3: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x9e0 net/core/dev.c:13022
3 locks held by kworker/u8:10/3442:
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc9000dba7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000dba7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
2 locks held by dhcpcd/5459:
#0: ffffffff8e8898f8 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5f1/0x790 net/socket.c:1337
#1: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:579
2 locks held by getty/5550:
#0: ffff88814eb4d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211
3 locks held by kworker/u8:18/6052:
#0: ffff88814da47938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88814da47938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc900055b7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc900055b7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194
1 lock held by syz.4.47/6223:
#0: ffff888030944480 (sb_writers#24){++++}-{0:0}, at: do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
#0: ffff888030944480 (sb_writers#24){++++}-{0:0}, at: do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
1 lock held by syz-executor/7175:
#0: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x5b7/0xd20 net/ipv6/addrconf.c:5027
1 lock held by syz-executor/7357:
#0: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
4 locks held by syz-executor/7365:
#0: ffff888034bb6480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline]
#0: ffff888034bb6480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682
#1: ffff88802aa12c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
#2: ffff888026870008 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888026870008 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
#3: ffffffff8e12c6b8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:184
7 locks held by syz-executor/7368:
#0: ffff888034bb6480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline]
#0: ffff888034bb6480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682
#1: ffff888053818078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
#2: ffff888026870008 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888026870008 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
#3: ffffffff8e12c6b8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:184
#4: ffff88801e2b20d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#4: ffff88801e2b20d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006
#5: ffff88801e2b1300 (&devlink->lock_key#16){+.+.}-{4:4}, at: nsim_drv_probe+0xc3/0xbd0 drivers/net/netdevsim/dev.c:1637
#6: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1049 [inline]
#6: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: nsim_create+0x800/0x1060 drivers/net/netdevsim/netdev.c:1143
2 locks held by syz-executor/7431:
#0: ffffffff8edb4958 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8edb4958 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8edb4958 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8e8a5878 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 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:346 [inline]
watchdog+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: bat_events batadv_dat_purge
RIP: 0010:__lock_acquire+0x32d/0x2cf0 kernel/locking/lockdep.c:5179
Code: 24 20 c1 e2 0f 0f b7 d2 09 f2 41 83 e5 03 41 c1 e5 10 41 09 d5 8b 54 24 10 83 e2 01 c1 e2 12 44 09 ea c1 e3 14 09 d3 8b 14 24 e2 13 41 c1 e4 15 41 09 d4 41 09 cc 41 09 dc 45 89 64 c7 20 41
RSP: 0018:ffffc90000ac7740 EFLAGS: 00000006
RAX: 0000000000000019 RBX: 0000000000040000 RCX: 0000000000000039
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000005 R08: ffffffff8ad3df8a R09: ffff88803d25b618
R10: dffffc0000000000 R11: fffffbfff1db668f R12: 0000000000000000
R13: 0000000000000000 R14: ffff88801c298000 R15: ffff88801c298b90
FS: 0000000000000000(0000) GS:ffff888126def000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc0ffd94e9c CR3: 000000000d3a8000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162
rtlock_slowlock kernel/locking/rtmutex.c:1894 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x14a/0x3e0 kernel/locking/spinlock_rt.c:57
spin_lock_bh include/linux/spinlock_rt.h:88 [inline]
__batadv_dat_purge+0x131/0x400 net/batman-adv/distributed-arp-table.c:173
batadv_dat_purge+0x20/0x70 net/batman-adv/distributed-arp-table.c:204
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246