INFO: task syz-executor:5793 blocked for more than 143 seconds.
Not tainted syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:22464 pid:5793 tgid:5793 ppid:1 task_flags:0x40014c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6908
__schedule_loop kernel/sched/core.c:6990 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7286
rwbase_write_lock+0x3da/0x730 kernel/locking/rwbase_rt.c:272
__super_lock fs/super.c:58 [inline]
__super_lock_excl fs/super.c:73 [inline]
deactivate_super+0xa9/0xe0 fs/super.c:508
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x70f/0x23c0 kernel/exit.c:976
do_group_exit+0x21b/0x2d0 kernel/exit.c:1118
__do_sys_exit_group kernel/exit.c:1129 [inline]
__se_sys_exit_group kernel/exit.c:1127 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1127
x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
do_sysca[ 372.190704][ T38] do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_sysca[ 372.190704][ T38] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f52a4dac799
RSP: 002b:00007fff155ef678 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f52a4e420d4 RCX: 00007f52a4dac799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000005 R08: 0000000000000000 R09: 00007f52a4e42050
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff155f0930
R13: 00007f52a4e42050 R14: 0000555579b914e8 R15: 00007fff155f2af0
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8ddcb880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcb880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcb880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:2/40:
#0: ffff88806321d138 ((wq_completion)loop7){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88806321d138 ((wq_completion)loop7){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc90000b17c40 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc90000b17c40 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
#2: ffff888026370160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:96 [inline]
#2: ffff888026370160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_process_work+0x125/0x11b0 drivers/block/loop.c:1953
2 locks held by kworker/u8:3/57:
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc9000123fc40 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc9000123fc40 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
2 locks held by kworker/u8:4/68:
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc9000153fc40 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc9000153fc40 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
3 locks held by kworker/u8:6/158:
#0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc90003a17c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc90003a17c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
#2: ffffffff8ddd1af0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
3 locks held by kworker/u8:7/172:
#0: ffff8880320c5938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff8880320c5938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc90003b47c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc90003b47c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
#2: ffffffff8f159ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f159ff8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4198
5 locks held by kworker/u8:8/176:
2 locks held by getty/5551:
#0: ffff8880373cd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5793:
#0: ffff88802bf6a0d0 (&type->s_umount_key#61){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88802bf6a0d0 (&type->s_umount_key#61){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88802bf6a0d0 (&type->s_umount_key#61){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
5 locks held by udevd/5965:
4 locks held by syz.2.219/7223:
3 locks held by kworker/u8:14/8380:
#0: ffff88803214b138 ((wq_completion)loop6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88803214b138 ((wq_completion)loop6){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc90005dcfc40 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc90005dcfc40 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
#2: ffff88802635d160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:96 [inline]
#2: ffff88802635d160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_process_work+0x125/0x11b0 drivers/block/loop.c:1953
1 lock held by syz-executor/8728:
#0: ffffffff8f159ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f159ff8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x65f/0xe30 net/ipv6/addrconf.c:5031
1 lock held by syz-executor/8877:
9 locks held by syz.7.476/9257:
2 locks held by udevadm/9283:
3 locks held by syz.6.478/9289:
#0: ffff88805ee720d0 (&type->s_umount_key#55/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345
#1: ffffffff8ddcb880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#1: ffffffff8ddcb880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#1: ffffffff8ddcb880 (rcu_read_lock){....}-{1:3}, at: blk_mq_dispatch_queue_requests+0x552/0x800 block/blk-mq.c:2908
#2: ffff88802635d160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:96 [inline]
#2: ffff88802635d160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_queue_work drivers/block/loop.c:803 [inline]
#2: ffff88802635d160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_queue_rq+0x23c/0xb00 drivers/block/loop.c:1889
7 locks held by dhcpcd-run-hook/9291:
=============================================
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 02/27/2026
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: 176 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026
Workqueue: bat_events batadv_dat_purge
RIP: 0010:trace_hardirqs_off+0x2f/0x40 kernel/trace/trace_preemptirq.c:109
Code: 48 8b 5c 24 08 48 89 df e8 9e 14 56 09 65 8b 05 07 ea 82 10 85 c0 74 07 5b e9 3d d3 59 09 cc 65 c7 05 f1 e9 82 10 01 00 00 00 <48> 89 df 5b e9 68 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90
RSP: 0018:ffffc90003c47a40 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff8187ceba RCX: 0000000000000046
RDX: 00000000aa4c11c9 RSI: ffffffff8d55f1ba RDI: ffffffff8ba65e80
RBP: 0000000000000400 R08: ffffffff8187ca1c R09: ffffffff8ddcb880
R10: 0000000000000000 R11: fffffbfff1ed4617 R12: 0000000000000286
R13: dffffc0000000000 R14: ffff8880600cd7b8 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff88812633f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4ceaea0000 CR3: 000000003893c000 CR4: 00000000003526f0
Call Trace:
__local_bh_enable_ip+0xaa/0x2b0 kernel/softirq.c:270
local_bh_enable include/linux/bottom_half.h:33 [inline]
spin_unlock_bh include/linux/spinlock_rt.h:116 [inline]
__batadv_dat_purge+0x344/0x400 net/batman-adv/distributed-arp-table.c:185
batadv_dat_purge+0x20/0x70 net/batman-adv/distributed-arp-table.c:204
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358
worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
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