INFO: task dhcpcd:3933 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:dhcpcd state:D stack:20960 pid:3933 ppid:3932 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 percpu_rwsem_wait+0x2bd/0x300 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xda/0x120 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:748 [inline] cgroup_css_set_fork kernel/cgroup/cgroup.c:6432 [inline] cgroup_can_fork+0xc27/0xd30 kernel/cgroup/cgroup.c:6565 copy_process+0x248b/0x4020 kernel/fork.c:2446 kernel_clone+0x225/0x8b0 kernel/fork.c:2757 __do_sys_clone kernel/fork.c:2898 [inline] __se_sys_clone kernel/fork.c:2882 [inline] __x64_sys_clone+0x17c/0x1d0 kernel/fork.c:2882 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f7d11c04636 RSP: 002b:00007fffd14fcb70 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fffd14fcb78 RCX: 00007f7d11c04636 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007fffd151d0c0 R08: 0000000000000000 R09: 0000000000000001 R10: 00007f7d11b30a10 R11: 0000000000000246 R12: 00007fffd14fccb0 R13: 0000000000000000 R14: 0000000000000000 R15: 000055992bab9ac0 INFO: task syz-executor:4398 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:24832 pid:4398 ppid:4296 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 percpu_rwsem_wait+0x2bd/0x300 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xda/0x120 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:748 [inline] exit_signals+0x3c0/0x4f0 kernel/signal.c:2963 do_exit+0x578/0x2400 kernel/exit.c:827 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 get_signal+0x1272/0x1350 kernel/signal.c:2871 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fbb9a784fd3 RSP: 002b:00007ffc43797818 EFLAGS: 00000202 ORIG_RAX: 000000000000003d RAX: fffffffffffffe00 RBX: 0000000000001130 RCX: 00007fbb9a784fd3 RDX: 0000000040000000 RSI: 00007ffc4379782c RDI: 00000000ffffffff RBP: 00007ffc4379782c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffc437978b0 R13: 00007ffc437978b8 R14: 0000000000000009 R15: 0000000000000000 INFO: task syz-executor:4402 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21480 pid:4402 ppid:4399 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 rwsem_down_write_slowpath+0xbed/0x1090 kernel/locking/rwsem.c:1189 mmap_write_lock include/linux/mmap_lock.h:71 [inline] mpol_rebind_mm+0xbe/0x370 mm/mempolicy.c:386 cpuset_attach+0x284/0x540 kernel/cgroup/cpuset.c:2663 cgroup_migrate_execute+0x7a3/0xf30 kernel/cgroup/cgroup.c:2662 cgroup_attach_task+0x558/0x840 kernel/cgroup/cgroup.c:2953 __cgroup1_procs_write+0x2e0/0x3e0 kernel/cgroup/cgroup-v1.c:522 cgroup_file_write+0x2f8/0x660 kernel/cgroup/cgroup.c:4100 kernfs_fop_write_iter+0x3b2/0x520 fs/kernfs/file.c:352 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x44c/0x960 fs/read_write.c:584 ksys_write+0x143/0x240 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f0930b8d97f RSP: 002b:00007ffcf34b7720 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f0930b8d97f RDX: 0000000000000001 RSI: 00007ffcf34b7770 RDI: 0000000000000003 RBP: 00007ffcf34b7ce0 R08: 0000000000000000 R09: 00007ffcf34b7577 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007ffcf34b7770 R14: 00007ffcf34b7ca0 R15: 00007ffcf34b7ce0 INFO: task syz-executor:4409 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:22144 pid:4409 ppid:4404 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747 cgroup_lock include/linux/cgroup.h:442 [inline] cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1700 __cgroup_procs_write+0x73/0x350 kernel/cgroup/cgroup.c:5174 cgroup_procs_write+0x23/0x40 kernel/cgroup/cgroup.c:5214 cgroup_file_write+0x2f8/0x660 kernel/cgroup/cgroup.c:4100 kernfs_fop_write_iter+0x3b2/0x520 fs/kernfs/file.c:352 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x44c/0x960 fs/read_write.c:584 ksys_write+0x143/0x240 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3c8a18d97f RSP: 002b:00007ffcee1cd3e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f3c8a18d97f RDX: 0000000000000001 RSI: 00007ffcee1cd430 RDI: 0000000000000003 RBP: 00007ffcee1cd9a0 R08: 0000000000000000 R09: 00007ffcee1cd237 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007ffcee1cd430 R14: 00007ffcee1cd960 R15: 00007ffcee1cd9a0 INFO: task syz-executor:4410 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:22144 pid:4410 ppid:4408 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747 cgroup_lock include/linux/cgroup.h:442 [inline] cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1700 __cgroup_procs_write+0x73/0x350 kernel/cgroup/cgroup.c:5174 cgroup_procs_write+0x23/0x40 kernel/cgroup/cgroup.c:5214 cgroup_file_write+0x2f8/0x660 kernel/cgroup/cgroup.c:4100 kernfs_fop_write_iter+0x3b2/0x520 fs/kernfs/file.c:352 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x44c/0x960 fs/read_write.c:584 ksys_write+0x143/0x240 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f636b18d97f RSP: 002b:00007ffd3f6f15f0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f636b18d97f RDX: 0000000000000001 RSI: 00007ffd3f6f1640 RDI: 0000000000000003 RBP: 00007ffd3f6f1bb0 R08: 0000000000000000 R09: 00007ffd3f6f1447 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007ffd3f6f1640 R14: 00007ffd3f6f1b70 R15: 00007ffd3f6f1bb0 INFO: task udevd:4440 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:26560 pid:4440 ppid:3638 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 percpu_rwsem_wait+0x2bd/0x300 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xda/0x120 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:748 [inline] exit_signals+0x3c0/0x4f0 kernel/signal.c:2963 do_exit+0x578/0x2400 kernel/exit.c:827 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 __do_sys_exit_group kernel/exit.c:1033 [inline] __se_sys_exit_group kernel/exit.c:1031 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f92ec8f16c5 RSP: 002b:00007ffef6f930d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000563ffcfe8ad0 RCX: 00007f92ec8f16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000563ffcfd5910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffef6f93120 R14: 0000000000000000 R15: 0000000000000000 INFO: task udevd:4441 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:26560 pid:4441 ppid:3638 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 percpu_rwsem_wait+0x2bd/0x300 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xda/0x120 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:748 [inline] exit_signals+0x3c0/0x4f0 kernel/signal.c:2963 do_exit+0x578/0x2400 kernel/exit.c:827 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 __do_sys_exit_group kernel/exit.c:1033 [inline] __se_sys_exit_group kernel/exit.c:1031 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f92ec8f16c5 RSP: 002b:00007ffef6f930d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000563ffcff9f80 RCX: 00007f92ec8f16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000563ffcfd5910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffef6f93120 R14: 0000000000000000 R15: 0000000000000000 INFO: task udevd:4442 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:26528 pid:4442 ppid:3638 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 percpu_rwsem_wait+0x2bd/0x300 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xda/0x120 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:748 [inline] exit_signals+0x3c0/0x4f0 kernel/signal.c:2963 do_exit+0x578/0x2400 kernel/exit.c:827 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 __do_sys_exit_group kernel/exit.c:1033 [inline] __se_sys_exit_group kernel/exit.c:1031 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f92ec8f16c5 RSP: 002b:00007ffef6f930d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000563ffcfff960 RCX: 00007f92ec8f16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000563ffcfd5910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffef6f93120 R14: 0000000000000000 R15: 0000000000000000 INFO: task udevd:4443 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:26560 pid:4443 ppid:3638 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 percpu_rwsem_wait+0x2bd/0x300 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xda/0x120 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:748 [inline] exit_signals+0x3c0/0x4f0 kernel/signal.c:2963 do_exit+0x578/0x2400 kernel/exit.c:827 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 __do_sys_exit_group kernel/exit.c:1033 [inline] __se_sys_exit_group kernel/exit.c:1031 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f92ec8f16c5 RSP: 002b:00007ffef6f930d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000563ffcffe6c0 RCX: 00007f92ec8f16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000563ffcfd5910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffef6f93120 R14: 0000000000000000 R15: 0000000000000000 INFO: task udevd:4444 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:26560 pid:4444 ppid:3638 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 percpu_rwsem_wait+0x2bd/0x300 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xda/0x120 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:748 [inline] exit_signals+0x3c0/0x4f0 kernel/signal.c:2963 do_exit+0x578/0x2400 kernel/exit.c:827 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 __do_sys_exit_group kernel/exit.c:1033 [inline] __se_sys_exit_group kernel/exit.c:1031 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f92ec8f16c5 RSP: 002b:00007ffef6f930d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000563ffcfe81a0 RCX: 00007f92ec8f16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000563ffcfd5910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffef6f93120 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2b570 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2bd90 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by kworker/u4:4/56: #0: ffff8880b8e3aad8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #1: ffff8880b8e27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x312/0x6d0 kernel/sched/psi.c:987 1 lock held by dhcpcd/3933: #0: ffffffff8cb53810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x248b/0x4020 kernel/fork.c:2446 2 locks held by getty/4033: #0: ffff88802f1a6098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198 1 lock held by syz-executor/4398: #0: ffffffff8cb53810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827 7 locks held by syz-executor/4402: #0: ffff888078e28460 (sb_writers#11){.+.+}-{0:0}, at: vfs_write+0x256/0x960 fs/read_write.c:580 #1: ffff888028284488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e3/0x520 fs/kernfs/file.c:343 #2: ffffffff8cb53628 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:442 [inline] #2: ffffffff8cb53628 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1700 #3: ffffffff8c9c7a70 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2476 [inline] #3: ffffffff8c9c7a70 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x183/0x600 kernel/cgroup/cgroup.c:2982 #4: ffffffff8cb53810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2478 [inline] #4: ffffffff8cb53810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x199/0x600 kernel/cgroup/cgroup.c:2982 #5: ffffffff8cb61ca8 (cpuset_mutex){+.+.}-{3:3}, at: cpuset_attach+0xac/0x540 kernel/cgroup/cpuset.c:2647 #6: ffff8880731053d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline] #6: ffff8880731053d8 (&mm->mmap_lock){++++}-{3:3}, at: mpol_rebind_mm+0xbe/0x370 mm/mempolicy.c:386 3 locks held by syz-executor/4409: #0: ffff888023e34460 (sb_writers#10){.+.+}-{0:0}, at: vfs_write+0x256/0x960 fs/read_write.c:580 #1: ffff88805a3db088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e3/0x520 fs/kernfs/file.c:343 #2: ffffffff8cb53628 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:442 [inline] #2: ffffffff8cb53628 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1700 3 locks held by syz-executor/4410: #0: ffff888023e34460 (sb_writers#10){.+.+}-{0:0}, at: vfs_write+0x256/0x960 fs/read_write.c:580 #1: ffff88805a3ccc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e3/0x520 fs/kernfs/file.c:343 #2: ffffffff8cb53628 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:442 [inline] #2: ffffffff8cb53628 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1700 2 locks held by syz-executor/4413: #0: ffffffff8cbc4f50 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:593 [inline] #0: ffffffff8cbc4f50 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1541 [inline] #0: ffffffff8cbc4f50 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x2a9/0x15c0 kernel/fork.c:1590 #1: ffff888073105b58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] #1: ffff888073105b58 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:594 [inline] #1: ffff888073105b58 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1541 [inline] #1: ffff888073105b58 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x2c3/0x15c0 kernel/fork.c:1590 1 lock held by udevd/4440: #0: ffffffff8cb53810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827 1 lock held by udevd/4441: #0: ffffffff8cb53810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827 1 lock held by udevd/4442: #0: ffffffff8cb53810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827 1 lock held by udevd/4443: #0: ffffffff8cb53810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827 1 lock held by udevd/4444: #0: ffffffff8cb53810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827 5 locks held by kworker/u4:8/4512: #0: ffff8880b8e3aad8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #1: ffff8880b8e27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x312/0x6d0 kernel/sched/psi.c:987 #2: ffff8880b8e28418 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999 #3: ffffffff96e8da48 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x6a/0x490 lib/debugobjects.c:698 #4: ffffffff8c9dc8c8 (text_mutex){+.+.}-{3:3}, at: arch_jump_label_transform_apply+0xe/0x20 arch/x86/kernel/jump_label.c:145 1 lock held by syz.0.26/4539: #0: ffff88807b216a58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline] #0: ffff88807b216a58 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x20f/0x8e0 mm/mmap.c:3258 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 56 Comm: kworker/u4:4 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:put_unaligned_le32 include/asm-generic/unaligned.h:47 [inline] RIP: 0010:chacha_block_generic+0x131/0xd20 lib/crypto/chacha.c:86 Code: 0f b6 04 10 84 c0 0f 85 51 05 00 00 45 03 2f 4c 8d 7b 08 4c 8d 63 0b 4c 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 57 05 00 00 <4c> 89 e0 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 6e 05 00 00 45 89 2f RSP: 0018:ffffc900015777a0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffffc900015778a0 RCX: 00000000a4c85b91 RDX: dffffc0000000000 RSI: ffffc900015777d4 RDI: ffffc900015777dc RBP: ffffc90001577830 R08: 000000000330940b R09: ffffc900015777d8 R10: 00000000b6253bb1 R11: 000000003a0aafab R12: ffffc900015778ab R13: 000000001e2a88c3 R14: ffffc90001577a20 R15: ffffc900015778a8 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c000069738 CR3: 000000002e35d000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: chacha20_block include/crypto/chacha.h:36 [inline] crng_fast_key_erasure drivers/char/random.c:259 [inline] crng_make_state+0x389/0xa90 drivers/char/random.c:352 _get_random_bytes+0xd2/0x210 drivers/char/random.c:366 eth_random_addr include/linux/etherdevice.h:232 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:756 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x364/0xaf0 drivers/net/netdevsim/dev.c:851 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295