INFO: task syz.8.1644:17541 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.1644 state:D stack:29024 pid:17541 tgid:17503 ppid:8517 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
inode_lock_nested include/linux/fs.h:1073 [inline]
lock_rename fs/namei.c:3762 [inline]
__start_renaming+0x148/0x410 fs/namei.c:3858
filename_renameat2+0x38c/0x9c0 fs/namei.c:6125
__do_sys_renameat2 fs/namei.c:6179 [inline]
__se_sys_renameat2+0x5a/0x2c0 fs/namei.c:6174
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c2ba4c819
RSP: 002b:00007f7c29c7d028 EFLAGS: 00000246 ORIG_RAX: 000000000000013c
RAX: ffffffffffffffda RBX: 00007f7c2bcc6090 RCX: 00007f7c2ba4c819
RDX: ffffffffffffff9c RSI: 0000200000000780 RDI: ffffffffffffff9c
RBP: 00007f7c2bae2c91 R08: 0000000000000002 R09: 0000000000000000
R10: 0000200000000680 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7c2bcc6128 R14: 00007f7c2bcc6090 R15: 00007fff46e211b8
INFO: task syz.8.1644:17545 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.1644 state:D stack:29024 pid:17545 tgid:17503 ppid:8517 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
inode_lock_nested include/linux/fs.h:1073 [inline]
__start_dirop fs/namei.c:2929 [inline]
start_dirop fs/namei.c:2940 [inline]
filename_create+0x200/0x370 fs/namei.c:4928
filename_mknodat+0x18c/0x670 fs/namei.c:5136
__do_sys_mknod fs/namei.c:5185 [inline]
__se_sys_mknod+0x3a/0x150 fs/namei.c:5182
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c2ba4c819
RSP: 002b:00007f7c29c5c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 00007f7c2bcc6180 RCX: 00007f7c2ba4c819
RDX: 0000000000000000 RSI: 0000000000001000 RDI: 0000200000000080
RBP: 00007f7c2bae2c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7c2bcc6218 R14: 00007f7c2bcc6180 R15: 00007fff46e211b8
Showing all locks held in the system:
4 locks held by kworker/u8:0/12:
#0: ffff88801eace138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline]
#0: ffff88801eace138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371
#1: ffffc90000117c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline]
#1: ffffc90000117c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371
#2: ffff88802ac440d0 (&type->s_umount_key#57){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff8880611f6368 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
1 lock held by khungtaskd/38:
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5555:
#0: ffff88803787f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e732e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by udevd/5958:
4 locks held by syz.8.1644/17513:
2 locks held by syz.8.1644/17541:
#0: ffff88802ac44480 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff8880611f6738 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff8880611f6738 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3762 [inline]
#1: ffff8880611f6738 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: __start_renaming+0x148/0x410 fs/namei.c:3858
2 locks held by syz.8.1644/17545:
#0: ffff88802ac44480 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff8880611f6738 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff8880611f6738 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2929 [inline]
#1: ffff8880611f6738 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2940 [inline]
#1: ffff8880611f6738 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4928
3 locks held by syz-executor/17764:
2 locks held by syz.2.1702/17964:
#0: ffff88802ac440d0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff88802ac440d0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
#1: ffff888025d968c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:398 [inline]
#1: ffff888025d968c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x209/0xc30 fs/fs-writeback.c:2940
4 locks held by kworker/u8:12/18831:
3 locks held by syz.7.1875/19370:
2 locks held by syz.0.1877/19356:
2 locks held by syz.4.1878/19374:
4 locks held by rm/19397:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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:161 [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+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 18831 Comm: kworker/u8:12 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
RIP: 0010:unwind_get_return_address+0x56/0x90 arch/x86/kernel/unwind_orc.c:385
Code: 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 74 08 48 89 df e8 ab 31 b4 00 48 8b 3b e8 b3 6e 19 00 85 c0 74 14 43 80 3c 37 00 <74> 08 48 89 df e8 90 31 b4 00 48 8b 03 eb 02 31 c0 5b 41 5e 41 5f
RSP: 0000:ffffc90004d2eba8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc90004d2ec10 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff8d7c20ba RDI: ffffffff88f93b6f
RBP: ffffc90004d2ec50 R08: ffffc90004d2f3c8 R09: 0000000000000000
R10: ffffc90004d2ec18 R11: fffff520009a5d85 R12: ffff88802e889e80
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920009a5d82
FS: 0000000000000000(0000) GS:ffff888126332000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f835b2dd000 CR3: 000000002b126000 CR4: 00000000003526f0
Call Trace:
arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26
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
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2685 [inline]
slab_free mm/slub.c:6165 [inline]
kfree+0x1c1/0x6c0 mm/slub.c:6483
skb_kfree_head net/core/skbuff.c:1086 [inline]
skb_free_head net/core/skbuff.c:1098 [inline]
skb_release_data+0x6c3/0x8f0 net/core/skbuff.c:1125
skb_release_all net/core/skbuff.c:1200 [inline]
__kfree_skb+0x5d/0x210 net/core/skbuff.c:1214
kfree_skb_reason include/linux/skbuff.h:1322 [inline]
__netif_receive_skb_core+0x2c10/0x31a0 net/core/dev.c:6155
__netif_receive_skb_one_core net/core/dev.c:6179 [inline]
__netif_receive_skb net/core/dev.c:6294 [inline]
process_backlog+0x35e/0xc60 net/core/dev.c:6645
__napi_poll+0xaf/0x580 net/core/dev.c:7709
napi_poll net/core/dev.c:7772 [inline]
net_rx_action+0x696/0xe00 net/core/dev.c:7929
handle_softirqs+0x1de/0x6f0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
__local_bh_enable_ip+0x170/0x2b0 kernel/softirq.c:302
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline]
__dev_queue_xmit+0x1ebb/0x39b0 net/core/dev.c:4890
dev_queue_xmit include/linux/netdevice.h:3385 [inline]
batadv_send_skb_packet+0x418/0x690 net/batman-adv/send.c:100
batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:391 [inline]
batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline]
batadv_iv_send_outstanding_bat_ogm_packet+0x631/0x7e0 net/batman-adv/bat_iv_ogm.c:1700
process_one_work kernel/workqueue.c:3288 [inline]
process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3371
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3452
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245