INFO: task kworker/u4:1:144 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:1 state:D stack:22424 pid: 144 ppid: 2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2093
do_wait_for_common+0x2a2/0x450 kernel/sched/completion.c:85
__wait_for_common kernel/sched/completion.c:106 [inline]
wait_for_common kernel/sched/completion.c:117 [inline]
wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
kthread_stop+0x16e/0x540 kernel/kthread.c:666
destroy_workqueue+0xf2/0xb20 kernel/workqueue.c:4451
bond_destructor+0x49/0xa0 drivers/net/bonding/bond_main.c:5455
netdev_run_todo+0x851/0xa70 net/core/dev.c:10717
default_device_exit_batch+0x369/0x3c0 net/core/dev.c:11694
ops_exit_list net/core/net_namespace.c:177 [inline]
cleanup_net+0x791/0xba0 net/core/net_namespace.c:635
process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
INFO: task udevd:4856 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:26040 pid: 4856 ppid: 3562 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2e6/0x320 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x25e/0x20c0 kernel/exit.c:830
do_group_exit+0x12e/0x300 kernel/exit.c:997
__do_sys_exit_group kernel/exit.c:1008 [inline]
__se_sys_exit_group kernel/exit.c:1006 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7facdd9bf6c5
RSP: 002b:00007ffe542ca218 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000055f0f61dbad0 RCX: 00007facdd9bf6c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 000055f0f61c8910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe542ca260 R14: 0000000000000000 R15: 0000000000000000
INFO: task udevd:4884 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:27280 pid: 4884 ppid: 3562 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2e6/0x320 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x25e/0x20c0 kernel/exit.c:830
do_group_exit+0x12e/0x300 kernel/exit.c:997
__do_sys_exit_group kernel/exit.c:1008 [inline]
__se_sys_exit_group kernel/exit.c:1006 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7facdd9bf6c5
RSP: 002b:00007ffe542ca218 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000055f0f61d9d60 RCX: 00007facdd9bf6c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 000055f0f61c8910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe542ca260 R14: 0000000000000000 R15: 0000000000000000
INFO: task bond0:4905 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:bond0 state:D stack:29872 pid: 4905 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2e6/0x320 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x25e/0x20c0 kernel/exit.c:830
kthread_exit+0x11/0x20 kernel/kthread.c:283
kthread+0x454/0x520 kernel/kthread.c:336
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
INFO: task syz-executor:4949 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21456 pid: 4949 ppid: 4947 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
rwsem_down_write_slowpath+0xc87/0x1260 kernel/locking/rwsem.c:1165
mmap_write_lock include/linux/mmap_lock.h:71 [inline]
mpol_rebind_mm+0x33/0x2c0 mm/mempolicy.c:381
cpuset_attach+0x336/0x620 kernel/cgroup/cpuset.c:2376
cgroup_migrate_execute+0x7eb/0x1010 kernel/cgroup/cgroup.c:2598
cgroup_attach_task+0x53e/0x7b0 kernel/cgroup/cgroup.c:2893
__cgroup1_procs_write+0x2ee/0x3f0 kernel/cgroup/cgroup-v1.c:527
cgroup_file_write+0x2c3/0x660 kernel/cgroup/cgroup.c:3967
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2173 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x745/0xd60 fs/read_write.c:594
ksys_write+0x152/0x260 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0c43735e0e
RSP: 002b:00007ffef4b7b498 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000555585df4500 RCX: 00007f0c43735e0e
RDX: 0000000000000001 RSI: 00007ffef4b7b520 RDI: 0000000000000003
RBP: 00007ffef4b7ba90 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffef4b7b520 R14: 00007ffef4b7ba50 R15: 00007ffef4b7ba90
INFO: task syz-executor:4951 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:27344 pid: 4951 ppid: 4851 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2e6/0x320 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x25e/0x20c0 kernel/exit.c:830
do_group_exit+0x12e/0x300 kernel/exit.c:997
get_signal+0x6ca/0x12c0 kernel/signal.c:2900
arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7efedd393757
RSP: 002b:00007ffec77ae0d0 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000555558f54500 RCX: 00007efedd393757
RDX: 0000000040000000 RSI: 00007ffec77ae12c RDI: ffffffffffffffff
RBP: 00007ffec77ae12c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffec77ae1b0
R13: 00007ffec77ae1b8 R14: 00007efedd4f1c80 R15: 0000000000000000
INFO: task syz-executor:4953 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21848 pid: 4953 ppid: 4948 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1662
__cgroup_procs_write+0x73/0x350 kernel/cgroup/cgroup.c:5013
cgroup_procs_write+0x23/0x40 kernel/cgroup/cgroup.c:5053
cgroup_file_write+0x2c3/0x660 kernel/cgroup/cgroup.c:3967
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2173 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x745/0xd60 fs/read_write.c:594
ksys_write+0x152/0x260 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f13960a0e0e
RSP: 002b:00007ffe99cc6238 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00005555773f1500 RCX: 00007f13960a0e0e
RDX: 0000000000000001 RSI: 00007ffe99cc62c0 RDI: 0000000000000003
RBP: 00007ffe99cc6830 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffe99cc62c0 R14: 00007ffe99cc67f0 R15: 00007ffe99cc6830
INFO: task syz-executor:4955 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21808 pid: 4955 ppid: 4952 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1662
__cgroup_procs_write+0x73/0x350 kernel/cgroup/cgroup.c:5013
cgroup_procs_write+0x23/0x40 kernel/cgroup/cgroup.c:5053
cgroup_file_write+0x2c3/0x660 kernel/cgroup/cgroup.c:3967
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2173 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x745/0xd60 fs/read_write.c:594
ksys_write+0x152/0x260 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fbc5b7e1e0e
RSP: 002b:00007ffeb7ee5db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000055555c306500 RCX: 00007fbc5b7e1e0e
RDX: 0000000000000001 RSI: 00007ffeb7ee5e40 RDI: 0000000000000003
RBP: 00007ffeb7ee63b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffeb7ee5e40 R14: 00007ffeb7ee6370 R15: 00007ffeb7ee63b0
INFO: task syz-executor:4956 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21720 pid: 4956 ppid: 4954 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1662
__cgroup_procs_write+0x73/0x350 kernel/cgroup/cgroup.c:5013
cgroup_procs_write+0x23/0x40 kernel/cgroup/cgroup.c:5053
cgroup_file_write+0x2c3/0x660 kernel/cgroup/cgroup.c:3967
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2173 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x745/0xd60 fs/read_write.c:594
ksys_write+0x152/0x260 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd432dd5e0e
RSP: 002b:00007ffda4e6ea78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00005555681c8500 RCX: 00007fd432dd5e0e
RDX: 0000000000000001 RSI: 00007ffda4e6eb00 RDI: 0000000000000003
RBP: 00007ffda4e6f070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffda4e6eb00 R14: 00007ffda4e6f030 R15: 00007ffda4e6f070
INFO: task udevd:4966 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:26992 pid: 4966 ppid: 3562 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
percpu_rwsem_wait+0x2e6/0x320 kernel/locking/percpu-rwsem.c:160
__percpu_down_read+0xc9/0x100 kernel/locking/percpu-rwsem.c:174
percpu_down_read include/linux/percpu-rwsem.h:65 [inline]
cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:724 [inline]
exit_signals+0x3e5/0x510 kernel/signal.c:2991
do_exit+0x25e/0x20c0 kernel/exit.c:830
do_group_exit+0x12e/0x300 kernel/exit.c:997
__do_sys_exit_group kernel/exit.c:1008 [inline]
__se_sys_exit_group kernel/exit.c:1006 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7facdd9bf6c5
RSP: 002b:00007ffe542ca218 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000055f0f61f2340 RCX: 00007facdd9bf6c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 000055f0f61c8910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe542ca260 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c31eb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/u4:1/144:
#0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000171fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffffffff8d431510 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589
2 locks held by udevd/3562:
#0: ffffffff8c3a8c10 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c3a8c10 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c3a8c10 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x22c/0x13f0 kernel/fork.c:1518
#1: ffff88807d6f6328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88807d6f6328 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88807d6f6328 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88807d6f6328 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x249/0x13f0 kernel/fork.c:1518
2 locks held by getty/3951:
#0: ffff88802c194098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
1 lock held by udevd/4856:
#0: ffffffff8c3445f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x25e/0x20c0 kernel/exit.c:830
1 lock held by udevd/4884:
#0: ffffffff8c3445f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x25e/0x20c0 kernel/exit.c:830
1 lock held by bond0/4905:
#0: ffffffff8c3445f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x25e/0x20c0 kernel/exit.c:830
7 locks held by syz-executor/4949:
#0: ffff8880797dc460 (sb_writers#11){.+.+}-{0:0}, at: vfs_write+0x295/0xd60 fs/read_write.c:590
#1: ffff8880791ae488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
#2: ffffffff8c344408 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1662
#3: ffffffff8c1bd250 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2411 [inline]
#3: ffffffff8c1bd250 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x196/0x5c0 kernel/cgroup/cgroup.c:2922
#4: ffffffff8c3445f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2413 [inline]
#4: ffffffff8c3445f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x1ac/0x5c0 kernel/cgroup/cgroup.c:2922
#5: ffffffff8c351f48 (cpuset_mutex){+.+.}-{3:3}, at: cpuset_attach+0xad/0x620 kernel/cgroup/cpuset.c:2348
#6: ffff888016c68f28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#6: ffff888016c68f28 (&mm->mmap_lock){++++}-{3:3}, at: mpol_rebind_mm+0x33/0x2c0 mm/mempolicy.c:381
1 lock held by syz-executor/4951:
#0: ffffffff8c3445f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x25e/0x20c0 kernel/exit.c:830
3 locks held by syz-executor/4953:
#0: ffff88807925c460 (sb_writers#10){.+.+}-{0:0}, at: vfs_write+0x295/0xd60 fs/read_write.c:590
#1: ffff88805b592088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
#2: ffffffff8c344408 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1662
3 locks held by syz-executor/4955:
#0: ffff88807925c460 (sb_writers#10){.+.+}-{0:0}, at: vfs_write+0x295/0xd60 fs/read_write.c:590
#1: ffff88805f2b0488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
#2: ffffffff8c344408 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1662
3 locks held by syz-executor/4956:
#0: ffff88807925c460 (sb_writers#10){.+.+}-{0:0}, at: vfs_write+0x295/0xd60 fs/read_write.c:590
#1: ffff888074c0bc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
#2: ffffffff8c344408 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1662
2 locks held by syz-executor/4962:
#0: ffffffff8c3a8c10 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c3a8c10 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c3a8c10 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x22c/0x13f0 kernel/fork.c:1518
#1: ffff888016c6c728 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff888016c6c728 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff888016c6c728 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff888016c6c728 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x249/0x13f0 kernel/fork.c:1518
1 lock held by udevd/4966:
#0: ffffffff8c3445f0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x25e/0x20c0 kernel/exit.c:830
2 locks held by dhcpcd-run-hook/5087:
#0: ffffffff8c3a8c10 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c3a8c10 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c3a8c10 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x22c/0x13f0 kernel/fork.c:1518
#1: ffff88807afd4728 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88807afd4728 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88807afd4728 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88807afd4728 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x249/0x13f0 kernel/fork.c:1518
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:729