INFO: task dhcpcd:3853 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:21376 pid: 3853 ppid: 3852 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 percpu_rwsem_wait+0x2d8/0x310 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] uprobe_start_dup_mmap+0x134/0x150 kernel/events/uprobes.c:1562 dup_mmap kernel/fork.c:503 [inline] dup_mm kernel/fork.c:1466 [inline] copy_mm+0x21f/0x1380 kernel/fork.c:1518 copy_process+0x17c6/0x3e00 kernel/fork.c:2290 kernel_clone+0x219/0x930 kernel/fork.c:2679 __do_sys_clone kernel/fork.c:2796 [inline] __se_sys_clone kernel/fork.c:2780 [inline] __x64_sys_clone+0x170/0x1c0 kernel/fork.c:2780 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: 0033:0x7eff2a6d8636 RSP: 002b:00007fff93f76f50 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fff93f76f58 RCX: 00007eff2a6d8636 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007fff93f974a0 R08: 0000000000000000 R09: 0000000000000001 R10: 00007eff2a604a10 R11: 0000000000000246 R12: 00007fff93f77090 R13: 0000000000000000 R14: 0000000000000000 R15: 000055df26a6cac0 INFO: task syz.8.9852:31239 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.9852 state:D stack:24584 pid:31239 ppid: 29417 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 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+0xc71/0x2390 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 _free_event+0x850/0xe60 kernel/events/core.c:5164 put_event kernel/events/core.c:5258 [inline] perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5383 perf_release+0x37/0x40 kernel/events/core.c:5393 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x61e/0x20a0 kernel/exit.c:883 do_group_exit+0x12e/0x300 kernel/exit.c:997 get_signal+0x6ca/0x12c0 kernel/signal.c:2900 arch_do_signal_or_restart+0xc1/0x1300 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: 0033:0x7f419cdecfc9 RSP: 002b:00007f419b0330e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f419d044098 RCX: 00007f419cdecfc9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f419d044098 RBP: 00007f419d044090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f419d044128 R14: 00007ffedc0d6a20 R15: 00007ffedc0d6b08 INFO: task syz.5.9864:31259 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.9864 state:D stack:27552 pid:31259 ppid: 29691 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 percpu_down_write+0x27c/0x2f0 kernel/locking/percpu-rwsem.c:238 register_for_each_vma+0x2f/0xbb0 kernel/events/uprobes.c:1041 __uprobe_register+0x500/0x750 kernel/events/uprobes.c:1182 trace_uprobe_enable kernel/trace/trace_uprobe.c:1066 [inline] probe_event_enable+0x3ed/0xca0 kernel/trace/trace_uprobe.c:1135 perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline] perf_trace_event_init+0x518/0xa10 kernel/trace/trace_event_perf.c:202 perf_uprobe_init+0x12a/0x190 kernel/trace/trace_event_perf.c:336 perf_uprobe_event_init+0xe2/0x170 kernel/events/core.c:10253 perf_try_init_event+0x12b/0x3d0 kernel/events/core.c:11601 perf_init_event kernel/events/core.c:11665 [inline] perf_event_alloc+0xfcf/0x2240 kernel/events/core.c:11957 __do_sys_perf_event_open kernel/events/core.c:12495 [inline] __se_sys_perf_event_open+0x6c5/0x1b80 kernel/events/core.c:12387 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: 0033:0x7f2e12edffc9 RSP: 002b:00007f2e11147038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f2e13136fa0 RCX: 00007f2e12edffc9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000001080 RBP: 00007f2e12f62f91 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2e13137038 R14: 00007f2e13136fa0 R15: 00007fff1c367fb8 INFO: task syz.5.9864:31260 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.9864 state:D stack:29088 pid:31260 ppid: 29691 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 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+0xc71/0x2390 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221 perf_tp_event_init+0x89/0x110 kernel/events/core.c:10102 perf_try_init_event+0x12b/0x3d0 kernel/events/core.c:11601 perf_init_event kernel/events/core.c:11665 [inline] perf_event_alloc+0xfcf/0x2240 kernel/events/core.c:11957 __do_sys_perf_event_open kernel/events/core.c:12495 [inline] __se_sys_perf_event_open+0x5ae/0x1b80 kernel/events/core.c:12387 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: 0033:0x7f2e12edffc9 RSP: 002b:00007f2e11126038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f2e13137090 RCX: 00007f2e12edffc9 RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000200000000240 RBP: 00007f2e12f62f91 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2e13137128 R14: 00007f2e13137090 R15: 00007fff1c367fb8 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by klogd/3549: #0: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 1 lock held by dhcpcd/3853: #0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline] #0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline] #0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518 2 locks held by getty/3951: #0: ffff88814c60a098 (&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+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 1 lock held by syz-executor/4171: #0: ffff88807a222428 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] #0: ffff88807a222428 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x15d/0x2b0 mm/util.c:549 2 locks held by syz-executor/22882: #0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline] #0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline] #0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518 #1: ffff888046b28f28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] #1: ffff888046b28f28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline] #1: ffff888046b28f28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline] #1: ffff888046b28f28 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518 2 locks held by syz-executor/30450: #0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline] #0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline] #0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518 #1: ffff88807a221d28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] #1: ffff88807a221d28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline] #1: ffff88807a221d28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline] #1: ffff88807a221d28 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518 1 lock held by syz.8.9852/31239: #0: ffffffff8c169e28 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 4 locks held by syz.5.9864/31259: #0: ffffffff96114918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313 #1: ffffffff8c169e28 (event_mutex){+.+.}-{3:3}, at: perf_uprobe_init+0x11f/0x190 kernel/trace/trace_event_perf.c:335 #2: ffff88806238e490 (&uprobe->register_rwsem){+.+.}-{3:3}, at: __uprobe_register+0x450/0x750 kernel/events/uprobes.c:1178 #3: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: register_for_each_vma+0x2f/0xbb0 kernel/events/uprobes.c:1041 2 locks held by syz.5.9864/31260: #0: ffffffff96114918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313 #1: ffffffff8c169e28 (event_mutex){+.+.}-{3:3}, at: perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221 ============================================= 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 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 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