INFO: task syz.0.872:11938 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.872 state:D stack:28896 pid:11938 tgid:11894 ppid:11164 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_mkdirat+0xd2/0x520 fs/namei.c:5265
__do_sys_mkdirat fs/namei.c:5293 [inline]
__se_sys_mkdirat+0x35/0x150 fs/namei.c:5290
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: 0033:0x7f1c291ab687
RSP: 002b:00007f1c273e4e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f1c273e4ee0 RCX: 00007f1c291ab687
RDX: 00000000000001ff RSI: 0000200000000100 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000200000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000100
R13: 00007f1c273e4ea0 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
1 lock held by khungtaskd/37:
#0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
7 locks held by kworker/u8:3/57:
4 locks held by kworker/u8:10/1297:
#0: ffff88801f6df138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff88801f6df138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc90005ccfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc90005ccfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffff888033c780d0 (&type->s_umount_key#59){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff888056c759a8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
2 locks held by getty/5563:
#0: ffff8880372a10a0 (&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
6 locks held by udevd/5804:
#0: ffff88802271be30 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline]
#0: ffff88802271be30 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:854
#1: ffff8880393aebb0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:611 [inline]
#1: ffff8880393aebb0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:441 [inline]
#1: ffff8880393aebb0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x36/0x340 mm/mmap_lock.c:501
#2: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#2: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#2: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:288
#3: ffff888029cf2958 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#3: ffff888029cf2958 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:402
#4: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#4: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#4: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#4: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#5: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#5: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x283/0xa90 mm/swap.c:-1
3 locks held by udevd/5941:
1 lock held by syz-executor/6773:
4 locks held by syz.0.872/11895:
2 locks held by syz.0.872/11938:
#0: ffff888033c78480 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff888056c75d78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff888056c75d78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2929 [inline]
#1: ffff888056c75d78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2940 [inline]
#1: ffff888056c75d78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4928
4 locks held by syz.7.1120/13593:
3 locks held by syz.6.1121/13605:
2 locks held by syz.8.1122/13608:
3 locks held by dhcpcd-run-hook/13619:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 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: 13608 Comm: syz.8.1122 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:trace_lock_release include/trace/events/lock.h:69 [inline]
RIP: 0010:lock_release+0x4b/0x3d0 kernel/locking/lockdep.c:5879
Code: 89 44 24 28 0f 1f 44 00 00 65 8b 05 73 38 ae 10 83 f8 08 0f 83 56 02 00 00 89 c0 48 0f a3 05 dc 02 ca 0d 73 0d e8 a5 19 09 00 <84> c0 0f 84 94 02 00 00 83 3d f6 15 ca 0d 00 0f 84 1c 02 00 00 65
RSP: 0018:ffffc90006c0f440 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000246 RCX: 0000000080000002
RDX: 0000000000000001 RSI: ffffffff8ba67660 RDI: ffffffff8ba67620
RBP: ffffc90006c0f5b8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000d81e84 R12: dffffc0000000000
R13: ffffffff8b2622c7 R14: ffff8880b8842a98 R15: ffff8880b8842a80
FS: 00007ffa06e166c0(0000) GS:ffff888126336000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f48159d7404 CR3: 000000002bb96000 CR4: 00000000003526f0
Call Trace:
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:176 [inline]
_raw_spin_unlock_irqrestore+0x1b/0x80 kernel/locking/spinlock.c:194
unlock_rt_mutex_safe kernel/locking/rtmutex.c:344 [inline]
rt_mutex_slowunlock+0x4a7/0x8b0 kernel/locking/rtmutex.c:1454
spin_unlock include/linux/spinlock_rt.h:109 [inline]
rmqueue_pcplist mm/page_alloc.c:3389 [inline]
rmqueue mm/page_alloc.c:3418 [inline]
get_page_from_freelist+0x9f9/0x2950 mm/page_alloc.c:3959
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2490
folio_alloc_mpol_noprof+0x39/0xe0 mm/mempolicy.c:2509
shmem_alloc_folio mm/shmem.c:1930 [inline]
shmem_alloc_and_add_folio mm/shmem.c:1972 [inline]
shmem_get_folio_gfp+0x644/0x1a80 mm/shmem.c:2567
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
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x629/0xba0 fs/read_write.c:688
ksys_write+0x156/0x270 fs/read_write.c:740
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: 0033:0x7ffa08b7d04e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ffa06e15da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ffa06e166c0 RCX: 00007ffa08b7d04e
RDX: 0000000001000000 RSI: 00007ff9fe9f6000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007ffa06e15ee0 R14: 00007ffa06e15ea0 R15: 00007ff9fe9f6000