INFO: task syz.3.199:7623 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.199 state:D stack:24392 pid:7623 tgid:7618 ppid:5799 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: 0033:0x7f0b32a3c819
RSP: 002b:00007f0b30c6d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 00007f0b32cb6090 RCX: 00007f0b32a3c819
RDX: 0000000000000706 RSI: 0000000000002000 RDI: 0000200000000200
RBP: 00007f0b32ad2c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b32cb6128 R14: 00007f0b32cb6090 R15: 00007ffffbece138
INFO: task syz.3.199:7630 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.199 state:D stack:26688 pid:7630 tgid:7618 ppid:5799 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
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 include/linux/fs.h:1028 [inline]
do_lock_mount+0x2b3/0x960 fs/namespace.c:2750
do_new_mount_fc fs/namespace.c:3781 [inline]
do_new_mount+0x483/0xd30 fs/namespace.c:3839
do_mount fs/namespace.c:4172 [inline]
__do_sys_mount fs/namespace.c:4361 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4338
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: 0033:0x7f0b32a3c819
RSP: 002b:00007f0b30c4c028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f0b32cb6180 RCX: 00007f0b32a3c819
RDX: 00002000000001c0 RSI: 0000200000003c40 RDI: 0000000000000000
RBP: 00007f0b32ad2c91 R08: 00002000000000c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b32cb6218 R14: 00007f0b32cb6180 R15: 00007ffffbece138
Showing all locks held in the system:
1 lock held by khungtaskd/37:
#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
4 locks held by kworker/u8:8/1105:
#0: ffff88801eabc138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff88801eabc138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc9000546fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc9000546fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffff88803adf80d0 (&type->s_umount_key#78){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff8880609a0ba8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
2 locks held by getty/5556:
#0: ffff8880373b80a0 (&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
4 locks held by syz.3.199/7619:
2 locks held by syz.3.199/7623:
#0: ffff88803adf8480 (sb_writers#23){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff8880609a0f78 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff8880609a0f78 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2929 [inline]
#1: ffff8880609a0f78 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2940 [inline]
#1: ffff8880609a0f78 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4928
1 lock held by syz.3.199/7630:
#0: ffff8880609a0f78 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff8880609a0f78 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: do_lock_mount+0x2b3/0x960 fs/namespace.c:2750
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7619 Comm: syz.3.199 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x54/0x80 kernel/kcov.c:222
Code: 09 f7 74 11 85 f6 75 39 85 d2 74 35 83 b9 74 16 00 00 00 74 2c 8b 91 50 16 00 00 83 fa 02 75 21 48 8b 91 58 16 00 00 48 8b 32 <48> 8d 7e 01 8b 89 54 16 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2
RSP: 0018:ffffc900057ff680 EFLAGS: 00000246
RAX: ffffffff8352aba6 RBX: 0000000000000004 RCX: ffff888029581e80
RDX: ffffc9000ec4b000 RSI: 000000000007ffff RDI: 0000000000000000
RBP: ffff888034111000 R08: 0000000000000000 R09: 0000000000000000
R10: 0030000000000000 R11: 000007ff00000020 R12: dffffc0000000000
R13: 1ffff11006822200 R14: 0000000000000000 R15: 1ffff11006822202
FS: 00007f0b30c8e6c0(0000) GS:ffff888126432000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562d419bd4f0 CR3: 000000004dd3c000 CR4: 00000000003526f0
Call Trace:
dtSplitRoot+0x7a6/0x16c0 fs/jfs/jfs_dtree.c:1981
dtSplitUp fs/jfs/jfs_dtree.c:993 [inline]
dtInsert+0xf19/0x5f10 fs/jfs/jfs_dtree.c:871
jfs_mkdir+0x783/0xb00 fs/jfs/namei.c:271
vfs_mkdir+0x40b/0x630 fs/namei.c:5239
filename_mkdirat+0x289/0x520 fs/namei.c:5272
__do_sys_mkdir fs/namei.c:5299 [inline]
__se_sys_mkdir+0x34/0x150 fs/namei.c:5296
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: 0033:0x7f0b32a3c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0b30c8e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f0b32cb5fa0 RCX: 00007f0b32a3c819
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000200000000340
RBP: 00007f0b32ad2c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b32cb6038 R14: 00007f0b32cb5fa0 R15: 00007ffffbece138