INFO: task syz.2.570:9880 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.570 state:D stack:25664 pid:9880 tgid:9878 ppid:7743 task_flags:0x400140 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
__rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1466 [inline]
down_read+0x132/0x200 kernel/locking/rwsem.c:1539
__super_lock fs/super.c:60 [inline]
super_lock+0x2d6/0x3d0 fs/super.c:122
__iterate_supers+0x126/0x290 fs/super.c:926
quota_sync_all fs/quota/quota.c:69 [inline]
__do_sys_quotactl fs/quota/quota.c:938 [inline]
__se_sys_quotactl+0x3a7/0x9e0 fs/quota/quota.c:917
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: 0033:0x7f3d2b17c799
RSP: 002b:00007f3d293ce028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f3d2b3f5fa0 RCX: 00007f3d2b17c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102
RBP: 00007f3d2b212c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3d2b3f6038 R14: 00007f3d2b3f5fa0 R15: 00007ffe3eb7a038
Showing all locks held in the system:
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
7 locks held by kworker/u8:5/79:
5 locks held by kworker/u8:9/165:
2 locks held by getty/5555:
#0: ffff888037b800a0 (&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 udevd/6052:
2 locks held by syz-executor/7654:
1 lock held by syz.2.570/9880:
#0: ffff8880251320d0 (&type->s_umount_key#69){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff8880251320d0 (&type->s_umount_key#69){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz.1.706/11084:
#0: ffff8880251320d0 (&type->s_umount_key#69){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff8880251320d0 (&type->s_umount_key#69){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz-executor/11292:
#0: ffff88804191e0d0 (&type->s_umount_key#89){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88804191e0d0 (&type->s_umount_key#89){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88804191e0d0 (&type->s_umount_key#89){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
1 lock held by syz.2.773/11807:
2 locks held by syz-executor/11833:
#0: ffffffff8f14c200 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577
#1: ffffffff8f15a9b8 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2d7/0x840 net/ipv4/ip_tunnel.c:1146
2 locks held by syz.4.779/11844:
5 locks held by sed/11850:
#0: ffff88803bd21d30 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:611 [inline]
#0: ffff88803bd21d30 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:441 [inline]
#0: ffff88803bd21d30 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x36/0x340 mm/mmap_lock.c:501
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:288
#2: ffff8880206b94d8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#2: ffff8880206b94d8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:402
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#4: ffff8880b8833f90 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#4: ffff8880b8833f90 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x283/0xa90 mm/swap.c:-1
=============================================
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 02/12/2026
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: 165 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: loop8 loop_workfn
RIP: 0010:__bfs_next kernel/locking/lockdep.c:1699 [inline]
RIP: 0010:__bfs kernel/locking/lockdep.c:1752 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x17af/0x2cf0 kernel/locking/lockdep.c:5237
Code: 48 89 05 f4 b7 b6 13 48 8d 84 24 90 00 00 00 48 89 05 e5 37 b6 13 31 ff 45 31 e4 4d 85 e4 4c 8b 6c 24 10 74 30 49 8b 44 24 30 <48> 85 c0 74 26 48 8b 40 10 48 83 c0 30 49 8b 0c 24 48 89 8c 24 d8
RSP: 0018:ffffc90003b96e30 EFLAGS: 00000082
RAX: ffffffff95daa768 RBX: 00000000000003cd RCX: 00000000000a1b85
RDX: ffffffff95da90a8 RSI: ffff888020374980 RDI: 00000000000003cd
RBP: f7c282750f16402a R08: ffffc90003b96df8 R09: 0000000000000020
R10: dffffc0000000000 R11: ffffffff81a0a3c0 R12: ffffffff95fe7268
R13: ffff888020374980 R14: ffff888020373d00 R15: 0000000000000490
FS: 0000000000000000(0000) GS:ffff88812633c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055dbd4ca3008 CR3: 000000006a7fa000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868
do_write_seqcount_begin_nested include/linux/seqlock.h:478 [inline]
do_write_seqcount_begin include/linux/seqlock.h:504 [inline]
psi_write_begin+0xab/0x160 kernel/sched/psi.c:183
psi_task_change+0xd4/0x340 kernel/sched/psi.c:919
psi_enqueue kernel/sched/stats.h:166 [inline]
enqueue_task+0x341/0x410 kernel/sched/core.c:2109
ttwu_runnable kernel/sched/core.c:3718 [inline]
try_to_wake_up+0x156/0x1380 kernel/sched/core.c:4160
rt_mutex_wake_up_q kernel/locking/rtmutex.c:566 [inline]
rt_mutex_slowunlock+0x5b8/0x8b0 kernel/locking/rtmutex.c:1469
spin_unlock include/linux/spinlock_rt.h:109 [inline]
__folio_batch_add_and_move+0x5d8/0xa90 mm/swap.c:201
folio_mark_accessed+0x36c/0x4a0 mm/swap.c:480
shmem_get_folio_gfp+0xbeb/0x1a80 mm/shmem.c:2519
shmem_get_folio mm/shmem.c:2673 [inline]
shmem_write_begin+0x166/0x320 mm/shmem.c:3327
generic_perform_write+0x2af/0x8b0 mm/filemap.c:4319
shmem_file_write_iter+0xfb/0x120 mm/shmem.c:3502
lo_rw_aio+0xc80/0xf00 include/linux/percpu-rwsem.h:-1
do_req_filebacked drivers/block/loop.c:433 [inline]
loop_handle_cmd drivers/block/loop.c:1925 [inline]
loop_process_work+0x637/0x11b0 drivers/block/loop.c:1960
process_one_work kernel/workqueue.c:3276 [inline]
process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
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