INFO: task syz.2.1067:8763 blocked for more than 144 seconds. Not tainted 6.6.100-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1067 state:D stack:23464 pid:8763 ppid:5787 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 perf_pending_task_sync kernel/events/core.c:5242 [inline] _free_event+0x174/0xf30 kernel/events/core.c:5248 put_event kernel/events/core.c:5376 [inline] perf_event_release_kernel+0x836/0x8c0 kernel/events/core.c:5501 perf_release+0x3b/0x40 kernel/events/core.c:5511 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1ce/0x250 kernel/task_work.c:239 get_signal+0x1235/0x1400 kernel/signal.c:2678 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f920bd8e9a9 RSP: 002b:00007f920cbc7fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffffc RBX: 00007f920bfb6080 RCX: 00007f920bd8e9a9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000043001000 RBP: 00007f920be10d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f920bfb6080 R15: 00007ffd466d1768 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8cd2fba0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2fba0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2fba0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5555: #0: ffff88802da330a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 2 locks held by syz.4.1608/10512: #0: ffffffff8dfae390 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x351/0x5e0 net/core/net_namespace.c:516 #1: ffffffff8cd35a40 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:4089 1 lock held by dhcpcd-run-hook/10646: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.6.100-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 10512 Comm: syz.4.1608 Not tainted 6.6.100-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:kasan_check_range+0x1c2/0x290 mm/kasan/generic.c:-1 Code: 5c 24 07 4d 85 e4 49 0f 49 dc 48 83 e3 f8 49 29 dc 74 12 41 80 3b 00 0f 85 a6 00 00 00 49 ff c3 49 ff cc 75 ee 5b 41 5c 41 5d <41> 5e 41 5f 5d c3 45 84 ff 75 61 41 f7 c7 00 ff 00 00 75 5d 41 f7 RSP: 0018:ffffc90000007840 EFLAGS: 00000056 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81678a8b RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e4a7da8 RBP: ffffc90000007970 R08: ffffffff8e4a7daf R09: 1ffffffff1c94fb5 R10: dffffc0000000000 R11: fffffbfff1c94fb6 R12: ffffffff81ac5774 R13: dffffc0000000000 R14: fffffbfff1c94fb6 R15: 1ffffffff1c94fb5 FS: 00007fc563c7d6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fda7caf4eb8 CR3: 000000005ef67000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:504 [inline] cpu_online include/linux/cpumask.h:1082 [inline] trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0xab/0x8b0 kernel/locking/lockdep.c:5765 rcu_lock_release include/linux/rcupdate.h:344 [inline] rcu_read_unlock include/linux/rcupdate.h:819 [inline] __perf_event_output kernel/events/core.c:7969 [inline] perf_event_output_forward+0x2f7/0x3a0 kernel/events/core.c:7978 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9703 perf_swevent_hrtimer+0x3bc/0x530 kernel/events/core.c:11173 __run_hrtimer kernel/time/hrtimer.c:1755 [inline] __hrtimer_run_queues+0x4df/0xc40 kernel/time/hrtimer.c:1819 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1881 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:check_kcov_mode kernel/kcov.c:193 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x36/0x80 kernel/kcov.c:320 Code: 30 20 7e 7e 65 8b 15 31 20 7e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 1c 16 00 00 00 74 4e 8b 91 f8 15 00 00 <83> fa 03 75 43 48 8b 91 00 16 00 00 44 8b 89 fc 15 00 00 49 c1 e1 RSP: 0018:ffffc900044774d8 EFLAGS: 00000246 RAX: ffffffff81c73c8b RBX: ffffea000147c648 RCX: ffff88802c228000 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900044776d0 R08: ffffffff8e4a7daf R09: 1ffffffff1c94fb5 R10: dffffc0000000000 R11: fffffbfff1c94fb6 R12: 00007fc5619f9000 R13: dffffc0000000000 R14: ffffea000147c640 R15: 0000000000000000 folio_test_anon include/linux/page-flags.h:679 [inline] PageAnon include/linux/page-flags.h:684 [inline] zap_pte_range mm/memory.c:1440 [inline] zap_pmd_range mm/memory.c:1570 [inline] zap_pud_range mm/memory.c:1599 [inline] zap_p4d_range mm/memory.c:1620 [inline] unmap_page_range+0xecb/0x2fe0 mm/memory.c:1641 unmap_vmas+0x25e/0x3a0 mm/memory.c:1731 exit_mmap+0x200/0xb50 mm/mmap.c:3298 __mmput+0x118/0x3c0 kernel/fork.c:1355 copy_process+0x294b/0x3d70 kernel/fork.c:2765 kernel_clone+0x21b/0x840 kernel/fork.c:2914 __do_sys_clone kernel/fork.c:3057 [inline] __se_sys_clone kernel/fork.c:3041 [inline] __x64_sys_clone+0x18c/0x1e0 kernel/fork.c:3041 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fc562d8e9a9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc563c7cfe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fc562fb5fa0 RCX: 00007fc562d8e9a9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000042164000 RBP: 00007fc562e10d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc562fb5fa0 R15: 00007ffe51174d38