INFO: task syz.0.17:5801 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:25368 pid:5801 tgid:5800 ppid:5582 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
do_uevent+0x2c3/0x570 fs/dlm/lockspace.c:206
new_lockspace fs/dlm/lockspace.c:583 [inline]
__dlm_new_lockspace+0x1aa4/0x2060 fs/dlm/lockspace.c:638
user_cluster_connect+0x231/0xcc0 fs/ocfs2/stack_user.c:976
ocfs2_cluster_connect+0x445/0x720 fs/ocfs2/stackglue.c:355
ocfs2_cluster_connect_agnostic+0x6e/0x90 fs/ocfs2/stackglue.c:385
user_dlm_register+0xd2/0x210 fs/ocfs2/dlmfs/userdlm.c:669
dlmfs_mkdir+0x13c/0x340 fs/ocfs2/dlmfs/dlmfs.c:434
vfs_mkdir+0x402/0x620 fs/namei.c:5276
filename_mkdirat+0x289/0x520 fs/namei.c:5309
__do_sys_mkdir fs/namei.c:5336 [inline]
__se_sys_mkdir+0x34/0x150 fs/namei.c:5333
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb9685de0d9
RSP: 002b:00007fb966836028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007fb968865fa0 RCX: 00007fb9685de0d9
RDX: 0000000000000000 RSI: 00000000000001ff RDI: 0000200000000640
RBP: 00007fb968675024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb968866038 R14: 00007fb968865fa0 R15: 00007ffc56805e58
INFO: task syz.4.21:5820 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.21 state:D stack:25672 pid:5820 tgid:5819 ppid:5592 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7607
rt_mutex_slowlock_block+0x55c/0x680 kernel/locking/rtmutex.c:1670
__rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1787 [inline]
rt_mutex_slowlock+0x2d4/0x780 kernel/locking/rtmutex.c:1827
__rt_mutex_lock kernel/locking/rtmutex.c:1842 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:560 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:578
__dlm_new_lockspace+0xa3/0x2060 fs/dlm/lockspace.c:632
device_create_lockspace+0xc7/0x350 fs/dlm/user.c:414
device_write+0x875/0xed0 fs/dlm/user.c:606
vfs_write+0x29f/0xbb0 fs/read_write.c:685
ksys_write+0x156/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa58f0ce0d9
RSP: 002b:00007fa58d326028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fa58f355fa0 RCX: 00007fa58f0ce0d9
RDX: 000000000000007d RSI: 0000200000001b00 RDI: 0000000000000008
RBP: 00007fa58f165024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa58f356038 R14: 00007fa58f355fa0 R15: 00007ffeb1b272c8
Showing all locks held in the system:
7 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/38:
#0: ffffffff8e1c3040 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e1c3040 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e1c3040 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by dhcpcd/5244:
#0: ffff88807cf08928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xe7/0xee0 net/netlink/af_netlink.c:2273
#1: ffffffff8f5ac938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f5ac938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dump_ifinfo+0xa74/0x14b0 net/core/rtnetlink.c:2562
2 locks held by getty/5334:
#0: ffff8880361040a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
3 locks held by syz.0.17/5801:
#0: ffff888063014500 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
#1: ffff8880624a5600 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline]
#1: ffff8880624a5600 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline]
#1: ffff8880624a5600 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline]
#1: ffff8880624a5600 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4955
#2: ffffffff99bcf498 (&ls_lock){+.+.}-{4:4}, at: __dlm_new_lockspace+0xa3/0x2060 fs/dlm/lockspace.c:632
1 lock held by dlm_recoverd/5805:
#0: ffff88801eb70d20 (&ls->ls_in_recovery){+.+.}-{4:4}, at: dlm_recoverd+0xba/0x23e0 fs/dlm/recoverd.c:400
1 lock held by syz.4.21/5820:
#0: ffffffff99bcf498 (&ls_lock){+.+.}-{4:4}, at: __dlm_new_lockspace+0xa3/0x2060 fs/dlm/lockspace.c:632
2 locks held by syz.7.48/6323:
#0: ffff888035bde500 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
#1: ffff8880624a4700 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline]
#1: ffff8880624a4700 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline]
#1: ffff8880624a4700 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline]
#1: ffff8880624a4700 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: filename_rmdir+0x1cd/0x520 fs/namei.c:5431
3 locks held by syz.7.48/6334:
#0: ffff888035bde500 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
#1: ffff8880624a4700 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline]
#1: ffff8880624a4700 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline]
#1: ffff8880624a4700 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline]
#1: ffff8880624a4700 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4955
#2: ffffffff99bcf498 (&ls_lock){+.+.}-{4:4}, at: __dlm_new_lockspace+0xa3/0x2060 fs/dlm/lockspace.c:632
4 locks held by syz-executor/6611:
#0: ffff888034d8e500 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#0: ffff888034d8e500 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888037078c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888028ebbe18 (kn->active#51){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888028ebbe18 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffffffff8ee21598 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234
4 locks held by syz-executor/6612:
#0: ffff888034d8e500 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#0: ffff888034d8e500 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff88806124e878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff888028ebbe18 (kn->active#51){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff888028ebbe18 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffffffff8ee21598 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234
10 locks held by syz-executor/6615:
3 locks held by syz-executor/6721:
1 lock held by syz-executor/6787:
#0: ffffffff8f5ac938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f5ac938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f5ac938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4158
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245