INFO: task syz.0.59:4424 blocked for more than 143 seconds. Not tainted 5.15.189-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.59 state:D stack:23552 pid: 4424 ppid: 4304 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127 _free_event+0x34/0xe60 kernel/events/core.c:5133 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 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 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: 0033:0x7fbdf802f9a9 RSP: 002b:00007ffd5ddaaca8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 000000000003b3ed RCX: 00007fbdf802f9a9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000001 R09: 000000035ddaaf9f R10: 00007fbdf7ea1000 R11: 0000000000000246 R12: 00007fbdf8256fac R13: 00007fbdf8256fa0 R14: ffffffffffffffff R15: 0000000000000006 Showing all locks held in the system: 4 locks held by kworker/u4:0/9: 1 lock held by khungtaskd/27: #0: ffffffff8c11c360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3949: #0: ffff88802bbcf098 (&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+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 4 locks held by syz.2.124/4611: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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 CPU: 0 PID: 4611 Comm: syz.2.124 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:127 [inline] RIP: 0010:seqcount_lockdep_reader_access+0x95/0x1c0 include/linux/seqlock.h:102 Code: e8 80 ca 0f 00 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 4c 8b 64 24 40 fa 4c 89 e6 48 81 e6 00 02 00 00 31 ff e8 3b ce 0f 00 <49> 81 e4 00 02 00 00 75 3d e8 4d ca 0f 00 48 8b 5d 08 48 c7 c7 48 RSP: 0018:ffffc900000079c0 EFLAGS: 00000006 RAX: ffffffff8167f9c5 RBX: 0000000000000000 RCX: ffff88802330bb80 RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000007a70 R08: dffffc0000000000 R09: fffffbfff1ad2dd6 R10: fffffbfff1ad2dd6 R11: 1ffffffff1ad2dd5 R12: 0000000000000006 R13: ffff88807d973d10 R14: 1ffff92000000f38 R15: dffffc0000000000 FS: 0000555583777500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000004 CR3: 000000001e4e1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] ktime_get+0x7b/0x270 kernel/time/timekeeping.c:831 hrtimer_forward_now include/linux/hrtimer.h:508 [inline] perf_swevent_hrtimer+0x461/0x530 kernel/events/core.c:10925 __run_hrtimer kernel/time/hrtimer.c:1690 [inline] __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline] RIP: 0010:lock_acquire+0x142/0x3f0 kernel/locking/lockdep.c:5619 Code: 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 f2 01 00 00 41 83 3e 00 0f 85 00 01 00 00 48 c7 84 24 a0 00 00 00 00 00 00 00 <9c> 8f 84 24 a0 00 00 00 4c 8b b4 24 a0 00 00 00 fa 48 c7 c7 c0 23 RSP: 0018:ffffc9000359f780 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: a3bf157a9613fb00 RDX: 0000000000000000 RSI: ffffffff8a599320 RDI: ffffffff8a5992e0 RBP: ffffc9000359f8a0 R08: dffffc0000000000 R09: fffffbfff1ad2dd6 R10: fffffbfff1ad2dd6 R11: 1ffffffff1ad2dd5 R12: ffffffff8c11c360 R13: 1ffff920006b3efc R14: ffff88802330c66c R15: dffffc0000000000 rcu_lock_acquire+0x20/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline] percpu_ref_tryget+0x12/0x150 include/linux/percpu-refcount.h:266 obj_cgroup_tryget include/linux/memcontrol.h:800 [inline] get_obj_cgroup_from_current+0x21a/0x2f0 mm/memcontrol.c:2930 memcg_slab_pre_alloc_hook mm/slab.h:283 [inline] slab_pre_alloc_hook+0x7e/0xc0 mm/slab.h:497 slab_alloc_node mm/slub.c:3134 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc_trace+0x47/0x2a0 mm/slub.c:3245 kmalloc include/linux/slab.h:604 [inline] alloc_fdtable+0xaf/0x280 fs/file.c:129 dup_fd+0x98b/0xcf0 fs/file.c:337 copy_files+0x72/0xe0 kernel/fork.c:1564 copy_process+0x1680/0x3e00 kernel/fork.c:2278 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: 0033:0x7f5c411bf9a9 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:00007ffcbb4d5318 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f5c413e6fa0 RCX: 00007f5c411bf9a9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000630c1000 RBP: 00007f5c41241d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f5c413e6fa0 R14: 00007f5c413e6fa0 R15: 0000000000000006