INFO: task syz-executor:5038 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:27344 pid: 5038 ppid: 4645 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 percpu_rwsem_wait+0x2ca/0x300 kernel/locking/percpu-rwsem.c:160 __percpu_down_read+0xc4/0x100 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:2992 do_exit+0x264/0x2110 kernel/exit.c:831 do_group_exit+0x12c/0x2f0 kernel/exit.c:998 get_signal+0x7eb/0x12e0 kernel/signal.c:2901 arch_do_signal_or_restart+0xe6/0x12a0 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: 0033:0x7fa4fa75c757 RSP: 002b:00007ffdc278cb40 EFLAGS: 00000202 ORIG_RAX: 000000000000003d RAX: fffffffffffffe00 RBX: 0000555571ead500 RCX: 00007fa4fa75c757 RDX: 0000000040000000 RSI: 00007ffdc278cb9c RDI: ffffffffffffffff RBP: 00007ffdc278cb9c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffdc278cc20 R13: 00007ffdc278cc28 R14: 00007fa4fa8bac80 R15: 0000000000000000 INFO: task syz-executor:5039 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:19680 pid: 5039 ppid: 5036 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 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+0xdf5/0x2400 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+0xe5/0x220 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+0x2c4/0x670 kernel/cgroup/cgroup.c:3967 kernfs_fop_write_iter+0x3a8/0x500 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+0x748/0xd70 fs/read_write.c:594 ksys_write+0x153/0x260 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: 0033:0x7f020ef95e0e RSP: 002b:00007fff48da8de8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000555562cb6500 RCX: 00007f020ef95e0e RDX: 0000000000000001 RSI: 00007fff48da8e70 RDI: 0000000000000003 RBP: 00007fff48da93e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff48da8e70 R14: 00007fff48da93a0 R15: 00007fff48da93e0 INFO: task syz-executor:5041 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:21584 pid: 5041 ppid: 5034 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 rwsem_down_write_slowpath+0xe63/0x13a0 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+0x333/0x610 kernel/cgroup/cpuset.c:2376 cgroup_migrate_execute+0x7ee/0xff0 kernel/cgroup/cgroup.c:2598 cgroup_attach_task+0x593/0x830 kernel/cgroup/cgroup.c:2893 __cgroup1_procs_write+0x2ea/0x3f0 kernel/cgroup/cgroup-v1.c:527 cgroup_file_write+0x2c4/0x670 kernel/cgroup/cgroup.c:3967 kernfs_fop_write_iter+0x3a8/0x500 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+0x748/0xd70 fs/read_write.c:594 ksys_write+0x153/0x260 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: 0033:0x7f930a455e0e RSP: 002b:00007ffc4066f1d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00005555792fd500 RCX: 00007f930a455e0e RDX: 0000000000000001 RSI: 00007ffc4066f260 RDI: 0000000000000003 RBP: 00007ffc4066f7d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc4066f260 R14: 00007ffc4066f790 R15: 00007ffc4066f7d0 INFO: task syz-executor:5052 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:20416 pid: 5052 ppid: 5051 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 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+0xdf5/0x2400 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+0xe5/0x220 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+0x2c4/0x670 kernel/cgroup/cgroup.c:3967 kernfs_fop_write_iter+0x3a8/0x500 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+0x748/0xd70 fs/read_write.c:594 ksys_write+0x153/0x260 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: 0033:0x7fd6d6df9e0e RSP: 002b:00007ffc5eb150b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000555588d7e500 RCX: 00007fd6d6df9e0e RDX: 0000000000000001 RSI: 00007ffc5eb15140 RDI: 0000000000000003 RBP: 00007ffc5eb156b0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc5eb15140 R14: 00007ffc5eb15670 R15: 00007ffc5eb156b0 INFO: task syz-executor:5055 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:22192 pid: 5055 ppid: 5042 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 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+0xdf5/0x2400 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+0xe5/0x220 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+0x2c4/0x670 kernel/cgroup/cgroup.c:3967 kernfs_fop_write_iter+0x3a8/0x500 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+0x748/0xd70 fs/read_write.c:594 ksys_write+0x153/0x260 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: 0033:0x7f36db24ee0e RSP: 002b:00007ffd0e4c6c38 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000555566502500 RCX: 00007f36db24ee0e RDX: 0000000000000001 RSI: 00007ffd0e4c6cc0 RDI: 0000000000000003 RBP: 00007ffd0e4c7230 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffd0e4c6cc0 R14: 00007ffd0e4c71f0 R15: 00007ffd0e4c7230 INFO: task udevd:5184 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:26832 pid: 5184 ppid: 3558 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 percpu_rwsem_wait+0x2ca/0x300 kernel/locking/percpu-rwsem.c:160 __percpu_down_read+0xc4/0x100 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:2992 do_exit+0x264/0x2110 kernel/exit.c:831 do_group_exit+0x12c/0x2f0 kernel/exit.c:998 __do_sys_exit_group kernel/exit.c:1009 [inline] __se_sys_exit_group kernel/exit.c:1007 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1007 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: 0033:0x7fcd5996a6c5 RSP: 002b:00007ffce3525478 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000555dd0f9ff80 RCX: 00007fcd5996a6c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000555dd0f7b910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffce35254c0 R14: 0000000000000000 R15: 0000000000000000 INFO: task udevd:5270 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:27504 pid: 5270 ppid: 3558 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 percpu_rwsem_wait+0x2ca/0x300 kernel/locking/percpu-rwsem.c:160 __percpu_down_read+0xc4/0x100 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:2992 do_exit+0x264/0x2110 kernel/exit.c:831 do_group_exit+0x12c/0x2f0 kernel/exit.c:998 __do_sys_exit_group kernel/exit.c:1009 [inline] __se_sys_exit_group kernel/exit.c:1007 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1007 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: 0033:0x7fcd5996a6c5 RSP: 002b:00007ffce3525478 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000555dd0fab820 RCX: 00007fcd5996a6c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000555dd0f7b910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffce35254c0 R14: 0000000000000000 R15: 0000000000000000 INFO: task udevd:5311 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:27696 pid: 5311 ppid: 3558 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 percpu_rwsem_wait+0x2ca/0x300 kernel/locking/percpu-rwsem.c:160 __percpu_down_read+0xc4/0x100 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:2992 do_exit+0x264/0x2110 kernel/exit.c:831 do_group_exit+0x12c/0x2f0 kernel/exit.c:998 __do_sys_exit_group kernel/exit.c:1009 [inline] __se_sys_exit_group kernel/exit.c:1007 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1007 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: 0033:0x7fcd5996a6c5 RSP: 002b:00007ffce3525478 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000555dd0f8cd60 RCX: 00007fcd5996a6c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000555dd0f7b910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffce35254c0 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c31ef20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by udevd/3558: #0: ffffffff8c3a8ed0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:504 [inline] #0: ffffffff8c3a8ed0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1467 [inline] #0: ffffffff8c3a8ed0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x229/0x13d0 kernel/fork.c:1519 #1: ffff88807da63228 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] #1: ffff88807da63228 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:505 [inline] #1: ffff88807da63228 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1467 [inline] #1: ffff88807da63228 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x247/0x13d0 kernel/fork.c:1519 2 locks held by getty/3946: #0: ffff88802c40f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158 1 lock held by syz-executor/5038: #0: ffffffff8c3449b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x264/0x2110 kernel/exit.c:831 3 locks held by syz-executor/5039: #0: ffff88814c990460 (sb_writers#10){.+.+}-{0:0}, at: vfs_write+0x296/0xd70 fs/read_write.c:590 #1: ffff88806031cc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x500 fs/kernfs/file.c:287 #2: ffffffff8c3447c8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xe5/0x220 kernel/cgroup/cgroup.c:1662 2 locks held by syz-executor/5040: #0: ffffffff8c3a8ed0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:504 [inline] #0: ffffffff8c3a8ed0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1467 [inline] #0: ffffffff8c3a8ed0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x229/0x13d0 kernel/fork.c:1519 #1: ffff88805e0e4028 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] #1: ffff88805e0e4028 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:505 [inline] #1: ffff88805e0e4028 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1467 [inline] #1: ffff88805e0e4028 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x247/0x13d0 kernel/fork.c:1519 7 locks held by syz-executor/5041: #0: ffff8881445b4460 (sb_writers#11){.+.+}-{0:0}, at: vfs_write+0x296/0xd70 fs/read_write.c:590 #1: ffff888078295088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x500 fs/kernfs/file.c:287 #2: ffffffff8c3447c8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xe5/0x220 kernel/cgroup/cgroup.c:1662 #3: ffffffff8c1bd6f0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2411 [inline] #3: ffffffff8c1bd6f0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x196/0x5c0 kernel/cgroup/cgroup.c:2922 #4: ffffffff8c3449b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2413 [inline] #4: ffffffff8c3449b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x1ac/0x5c0 kernel/cgroup/cgroup.c:2922 #5: ffffffff8c352308 (cpuset_mutex){+.+.}-{3:3}, at: cpuset_attach+0xad/0x610 kernel/cgroup/cpuset.c:2348 #6: ffff888024e90828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline] #6: ffff888024e90828 (&mm->mmap_lock){++++}-{3:3}, at: mpol_rebind_mm+0x33/0x2c0 mm/mempolicy.c:381 3 locks held by syz-executor/5052: #0: ffff88814c990460 (sb_writers#10){.+.+}-{0:0}, at: vfs_write+0x296/0xd70 fs/read_write.c:590 #1: ffff88807a520c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x500 fs/kernfs/file.c:287 #2: ffffffff8c3447c8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xe5/0x220 kernel/cgroup/cgroup.c:1662 3 locks held by syz-executor/5055: #0: ffff88814c990460 (sb_writers#10){.+.+}-{0:0}, at: vfs_write+0x296/0xd70 fs/read_write.c:590 #1: ffff8880608b9c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x500 fs/kernfs/file.c:287 #2: ffffffff8c3447c8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xe5/0x220 kernel/cgroup/cgroup.c:1662 1 lock held by udevd/5184: #0: ffffffff8c3449b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x264/0x2110 kernel/exit.c:831 1 lock held by udevd/5270: #0: ffffffff8c3449b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x264/0x2110 kernel/exit.c:831 1 lock held by udevd/5311: #0: ffffffff8c3449b0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x264/0x2110 kernel/exit.c:831 2 locks held by dhcpcd-run-hook/5455: #0: ffffffff8c3a8ed0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:504 [inline] #0: ffffffff8c3a8ed0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1467 [inline] #0: ffffffff8c3a8ed0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x229/0x13d0 kernel/fork.c:1519 #1: ffff88801affdc28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] #1: ffff88801affdc28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:505 [inline] #1: ffff88801affdc28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1467 [inline] #1: ffff88801affdc28 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x247/0x13d0 kernel/fork.c:1519 ============================================= 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 05/09/2026 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+0xe1b/0xe60 kernel/hung_task.c:369 kthread+0x42e/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 CPU: 0 PID: 5362 Comm: kworker/u4:6 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:168 [inline] RIP: 0010:unwind_next_frame+0x1a6/0x1cf0 arch/x86/kernel/unwind_orc.c:448 Code: 46 ff 39 e8 0f 86 56 14 00 00 89 e8 4c 8d 24 85 2c a0 9e 8e 4c 89 e0 48 c1 e8 03 49 bf 00 00 00 00 00 fc ff df 42 0f b6 04 38 <84> c0 0f 85 dd 15 00 00 45 8b 24 24 89 e8 ff c0 4c 8d 2c 85 2c a0 RSP: 0018:ffffc9000338f340 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffffc9000338f428 RCX: ffffffff962eff00 RDX: ffffc9000338f4b8 RSI: 0000000000090081 RDI: ffffffff81350ed7 RBP: 000000000000352d R08: ffffc9000338f401 R09: ffffc9000338f428 R10: dffffc0000000000 R11: fffff52000671e91 R12: ffffffff8e9f74e0 R13: ffffc9000338f3d8 R14: ffffffff81352d30 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000557f605a7048 CR3: 000000001bd8f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __unwind_start+0x51a/0x650 arch/x86/kernel/unwind_orc.c:704 unwind_start arch/x86/include/asm/unwind.h:60 [inline] arch_stack_walk+0xda/0x140 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xaf/0xe0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:612 [inline] kzalloc include/linux/slab.h:738 [inline] ieee802_11_parse_elems_crc+0xb3/0x1090 net/mac80211/util.c:1478 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2243 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1609 [inline] ieee80211_ibss_rx_queued_mgmt+0x36b/0x2b50 net/mac80211/ibss.c:1643 ieee80211_iface_process_skb net/mac80211/iface.c:1459 [inline] ieee80211_iface_work+0x714/0xc50 net/mac80211/iface.c:1513 cfg80211_wiphy_work+0x224/0x260 net/wireless/core.c:433 process_one_work+0x867/0xff0 kernel/workqueue.c:2310 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457 kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287