INFO: task syz.4.104:6321 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.104 state:D stack:22472 pid:6321 tgid:6317 ppid:5592 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x16d9/0x5700 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7668
rt_mutex_slowlock_block+0x55e/0x690 kernel/locking/rtmutex.c:1670
__rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1787 [inline]
rt_mutex_slowlock+0x2d4/0x780 kernel/locking/rtmutex.c:1827
__rt_mutex_lock kernel/locking/rtmutex.c:1842 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:562 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:580
devlink_health_report+0x305/0xb20 net/devlink/health.c:680
nsim_dev_health_break_write+0x197/0x240 drivers/net/netdevsim/health.c:162
full_proxy_write+0x127/0x1f0 fs/debugfs/file.c:389
vfs_write+0x29f/0xbb0 fs/read_write.c:685
ksys_write+0x156/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa77370e1d9
RSP: 002b:00007fa771924028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fa773996180 RCX: 00007fa77370e1d9
RDX: 0000000000000034 RSI: 00002000000002c0 RDI: 0000000000000007
RBP: 00007fa7737a5888 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa773996218 R14: 00007fa773996180 R15: 00007ffe1888fdb8
Showing all locks held in the system:
locks held by khungtaskd/39: 1, last CPU#1:
#0: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by kworker/u8:4/68: 6, on CPU#0:
#0: ffff88801beb0938 ((wq_completion)netns){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801beb0938 ((wq_completion)netns){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801beb0938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#0: ffff88801beb0938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#1: ffffc9000153fc40 (net_cleanup_work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc9000153fc40 (net_cleanup_work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc9000153fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#1: ffffc9000153fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#2: ffffffff905c7fc0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:677
#3: ffff888023366160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
#3: ffff888023366160 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline]
#3: ffff888023366160 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x420 net/devlink/core.c:581
#4: ffff88803cdde310 (&devlink->lock_key){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:314 [inline]
#4: ffff88803cdde310 (&devlink->lock_key){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:125 [inline]
#4: ffff88803cdde310 (&devlink->lock_key){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x142/0x420 net/devlink/core.c:581
#5: ffff88804238c318 (&sb->s_type->i_mutex_key#8/2){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline]
#5: ffff88804238c318 (&sb->s_type->i_mutex_key#8/2){+.+.}-{4:4}, at: __simple_recursive_removal+0x19a/0x520 fs/libfs.c:619
locks held by kworker/u8:11/1185: 3, on CPU#1:
#0: ffff88803414a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88803414a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88803414a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#0: ffff88803414a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#1: ffffc900069b7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc900069b7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc900069b7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#1: ffffc900069b7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#2: ffffffff905d67f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
#2: ffffffff905d67f8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x123/0x16e0 net/ipv6/addrconf.c:4230
locks held by kworker/u8:16/3341: 3, on CPU#1:
#0: ffff88813ff64138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88813ff64138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88813ff64138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#0: ffff88813ff64138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#1: ffffc90010077c40 ((linkwatch_work).work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90010077c40 ((linkwatch_work).work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90010077c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#1: ffffc90010077c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#2: ffffffff905d67f8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
locks held by getty/5342: 2, on CPU#0:
#0: ffff888037a5a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900044f32e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
locks held by syz-executor/5591: 4, last CPU#1:
#0: ffff88801278e510 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:527
#1: ffff888038926470 (&sb->s_type->i_lock_key){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#1: ffff888038926470 (&sb->s_type->i_lock_key){+.+.}-{3:3}, at: filemap_remove_folio+0xdb/0x3a0 mm/filemap.c:255
#2: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#2: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#2: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#2: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e2/0x400 kernel/locking/spinlock_rt.c:57
#3: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#3: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#3: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#3: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e2/0x400 kernel/locking/spinlock_rt.c:57
locks held by syz.4.104/6321: 3, on CPU#0:
#0: ffff88802b352928 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1259
#1: ffff88801fa8a510 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#1: ffff88801fa8a510 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#2: ffff88803cdde310 (&devlink->lock_key){+.+.}-{4:4}, at: devlink_health_report+0x305/0xb20 net/devlink/health.c:680
locks held by syz-executor/6957: 1, on CPU#1:
#0: ffffffff905d67f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
#0: ffffffff905d67f8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0 net/ipv4/devinet.c:978
locks held by syz-executor/6993: 1, on CPU#1:
#0: ffffffff905d67f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
#0: ffffffff905d67f8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x667/0xe00 net/ipv6/addrconf.c:5063
locks held by syz-executor/7110: 8, on CPU#1:
#0: ffff8880382f0510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2756 [inline]
#0: ffff8880382f0510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88807d7b0078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff88802a9f03c8 (kn->active#51){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff88802a9f03c8 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffffffff8fe46c18 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234
#4: ffff8880605bc160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
#4: ffff8880605bc160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
#4: ffff8880605bc160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb9/0x880 drivers/base/dd.c:1369
#5: ffff8880127de310 (&devlink->lock_key#13){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1724
#6: ffffffff905d67f8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x173/0x800 drivers/net/netdevsim/netdev.c:1193
#7: ffff888061a25060 (&dev_instance_lock_key#23){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2864 [inline]
#7: ffff888061a25060 (&dev_instance_lock_key#23){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline]
#7: ffff888061a25060 (&dev_instance_lock_key#23){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x11d0/0x2130 net/core/dev.c:12550
locks held by syz.8.192/7146: 3, last CPU#0:
#0: ffff888077e9e510 (sb_writers#5){.+.+}-{0:0}, at: do_coredump fs/coredump.c:1126 [inline]
#0: ffff888077e9e510 (sb_writers#5){.+.+}-{0:0}, at: vfs_coredump+0x376a/0x4520 fs/coredump.c:1195
#1: ffff88803f34c4b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:609 [inline]
#1: ffff88803f34c4b8 (&mm->mmap_lock){++++}-{4:4}, at: dump_user_range+0x1c5/0x12c0 fs/coredump.c:1349
#2: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#2: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#2: ffffffff8f1c3cc0 (rcu_read_lock){....}-{1:3}, at: mt_find+0x186/0x630 lib/maple_tree.c:6431
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [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:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
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: 3333 Comm: kworker/u8:15 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
RIP: 0010:stack_trace_consume_entry+0x0/0x280 kernel/stacktrace.c:83
Code: f0 5b 41 5e 5d c3 cc cc cc cc cc e8 2a 03 a9 09 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 18 48 ba 00 00
RSP: 0018:ffffc9000fd77320 EFLAGS: 00000286
RAX: ffffffff823365ee RBX: ffffc9000fd773e0 RCX: 0000000000000000
RDX: ffffc9000fd77301 RSI: ffffffff823365ee RDI: ffffc9000fd773e0
RBP: ffffc9000fd773b0 R08: ffffc9000fd77450 R09: 0000000000000000
R10: ffffc9000fd77378 R11: ffffffff81b18190 R12: ffff888034d5be80
R13: ffff8880b8446cd8 R14: ffffffff81b18190 R15: ffffc9000fd77328
FS: 0000000000000000(0000) GS:ffff8881249bb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd58d803ff8 CR3: 000000005f41e000 CR4: 00000000003526f0
Call Trace:
arch_stack_walk+0x10f/0x150 arch/x86/kernel/stacktrace.c:27
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:351 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:377
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4683 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
kmem_cache_alloc_noprof+0x360/0x690 mm/slub.c:5010
__build_skb+0x62/0x440 net/core/skbuff.c:494
__netdev_alloc_skb+0x19d/0x4b0 net/core/skbuff.c:807
__netdev_alloc_skb_ip_align include/linux/skbuff.h:3532 [inline]
netdev_alloc_skb_ip_align include/linux/skbuff.h:3542 [inline]
batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:643 [inline]
batadv_iv_ogm_queue_add+0x86c/0xd80 net/batman-adv/bat_iv_ogm.c:769
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:973 [inline]
batadv_iv_ogm_schedule+0xade/0xf90 net/batman-adv/bat_iv_ogm.c:1011
batadv_iv_send_outstanding_bat_ogm_packet+0x622/0x740 net/batman-adv/bat_iv_ogm.c:1924
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245