syzbot

FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
6.11.0-syzkaller-07337-g2004cef11ea0 #0 Not tainted
------------------------------------------------------
syz.2.116/5789 is trying to acquire lock:
ffffffff8e813f60 (console_owner){-...}-{0:0}, at: console_trylock_spinning kernel/printk/printk.c:2029 [inline]
ffffffff8e813f60 (console_owner){-...}-{0:0}, at: vprintk_emit+0x530/0xa10 kernel/printk/printk.c:2406

but task is already holding lock:
ffff8880b883e958 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:585

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&rq->__lock){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
       _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
       raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:585
       raw_spin_rq_lock kernel/sched/sched.h:1423 [inline]
       task_rq_lock+0xc6/0x360 kernel/sched/core.c:687
       cgroup_move_task+0x92/0x2d0 kernel/sched/psi.c:1161
       css_set_move_task+0x72e/0x950 kernel/cgroup/cgroup.c:898
       cgroup_post_fork+0x256/0x880 kernel/cgroup/cgroup.c:6683
       copy_process+0x3a2e/0x3d80 kernel/fork.c:2597
       kernel_clone+0x223/0x880 kernel/fork.c:2780
       user_mode_thread+0x132/0x1a0 kernel/fork.c:2858
       rest_init+0x23/0x300 init/main.c:712
       start_kernel+0x47f/0x500 init/main.c:1105
       x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
       x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:488
       common_startup_64+0x13e/0x147

-> #3 (&p->pi_lock){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline]
       try_to_wake_up+0xb0/0x1480 kernel/sched/core.c:4123
       __wake_up_common kernel/sched/wait.c:89 [inline]
       __wake_up_common_lock+0x130/0x1e0 kernel/sched/wait.c:106
       tty_port_default_wakeup+0xa6/0xf0 drivers/tty/tty_port.c:69
       serial8250_tx_chars+0x6e2/0x930 drivers/tty/serial/8250/8250_port.c:1821
       serial8250_handle_irq+0x630/0xb80 drivers/tty/serial/8250/8250_port.c:1929
       serial8250_default_handle_irq+0xd1/0x1f0 drivers/tty/serial/8250/8250_port.c:1949
       serial8250_interrupt+0xa9/0x1f0 drivers/tty/serial/8250/8250_core.c:86
       __handle_irq_event_percpu+0x29a/0xa80 kernel/irq/handle.c:158
       handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
       handle_irq_event+0x89/0x1f0 kernel/irq/handle.c:210
       handle_edge_irq+0x25f/0xc20 kernel/irq/chip.c:831
       generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
       handle_irq arch/x86/kernel/irq.c:247 [inline]
       call_irq_handler arch/x86/kernel/irq.c:259 [inline]
       __common_interrupt+0x136/0x230 arch/x86/kernel/irq.c:285
       common_interrupt+0xb4/0xd0 arch/x86/kernel/irq.c:278
       asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
       get_stack_info_noinstr+0x5/0x130 arch/x86/kernel/dumpstack_64.c:172
       get_stack_info+0x3c/0xf0 arch/x86/kernel/dumpstack_64.c:199
       __unwind_start+0x434/0x740 arch/x86/kernel/unwind_orc.c:729
       unwind_start arch/x86/include/asm/unwind.h:64 [inline]
       arch_stack_walk+0xe5/0x150 arch/x86/kernel/stacktrace.c:24
       stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
       save_stack+0xfb/0x1f0 mm/page_owner.c:156
       __set_page_owner+0x92/0x800 mm/page_owner.c:320
       set_page_owner include/linux/page_owner.h:32 [inline]
       post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1500
       prep_new_page mm/page_alloc.c:1508 [inline]
       get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3446
       __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4702
       alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263
       folio_alloc_mpol_noprof mm/mempolicy.c:2281 [inline]
       vma_alloc_folio_noprof+0x12e/0x230 mm/mempolicy.c:2312
       folio_prealloc+0x31/0x170
       wp_page_copy mm/memory.c:3350 [inline]
       do_wp_page+0x11cc/0x5310 mm/memory.c:3742
       handle_pte_fault+0x115e/0x7010 mm/memory.c:5552
       __handle_mm_fault mm/memory.c:5679 [inline]
       handle_mm_fault+0x1053/0x1ad0 mm/memory.c:5847
       do_user_addr_fault arch/x86/mm/fault.c:1338 [inline]
       handle_page_fault arch/x86/mm/fault.c:1481 [inline]
       exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

-> #2 (&tty->write_wait){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       __wake_up_common_lock+0x25/0x1e0 kernel/sched/wait.c:105
       tty_port_default_wakeup+0xa6/0xf0 drivers/tty/tty_port.c:69
       serial8250_tx_chars+0x6e2/0x930 drivers/tty/serial/8250/8250_port.c:1821
       serial8250_handle_irq+0x630/0xb80 drivers/tty/serial/8250/8250_port.c:1929
       serial8250_default_handle_irq+0xd1/0x1f0 drivers/tty/serial/8250/8250_port.c:1949
       serial8250_interrupt+0xa9/0x1f0 drivers/tty/serial/8250/8250_core.c:86
       __handle_irq_event_percpu+0x29a/0xa80 kernel/irq/handle.c:158
       handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
       handle_irq_event+0x89/0x1f0 kernel/irq/handle.c:210
       handle_edge_irq+0x25f/0xc20 kernel/irq/chip.c:831
       generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
       handle_irq arch/x86/kernel/irq.c:247 [inline]
       call_irq_handler arch/x86/kernel/irq.c:259 [inline]
       __common_interrupt+0x136/0x230 arch/x86/kernel/irq.c:285
       common_interrupt+0xb4/0xd0 arch/x86/kernel/irq.c:278
       asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
       _raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194
       spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
       uart_port_unlock_irqrestore include/linux/serial_core.h:782 [inline]
       uart_write+0x3e4/0xa40 drivers/tty/serial/serial_core.c:634
       process_output_block drivers/tty/n_tty.c:574 [inline]
       n_tty_write+0xd62/0x1230 drivers/tty/n_tty.c:2389
       iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
       file_tty_write+0x546/0x9b0 drivers/tty/tty_io.c:1096
       new_sync_write fs/read_write.c:590 [inline]
       vfs_write+0xa6d/0xc90 fs/read_write.c:683
       ksys_write+0x1a0/0x2c0 fs/read_write.c:736
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&port_lock_key){-.-.}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       uart_port_lock_irqsave include/linux/serial_core.h:711 [inline]
       serial8250_console_write+0x1a7/0x1ed0 drivers/tty/serial/8250/8250_port.c:3352
       console_emit_next_record kernel/printk/printk.c:3092 [inline]
       console_flush_all+0x86b/0xeb0 kernel/printk/printk.c:3180
       __console_flush_and_unlock kernel/printk/printk.c:3239 [inline]
       console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3279
       vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2407
       _printk+0xd5/0x120 kernel/printk/printk.c:2432
       register_console+0xbf5/0xfd0 kernel/printk/printk.c:4069
       univ8250_console_init+0x52/0x90 drivers/tty/serial/8250/8250_core.c:513
       console_init+0x1b8/0x6f0 kernel/printk/printk.c:4262
       start_kernel+0x2d8/0x500 init/main.c:1040
       x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
       x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:488
       common_startup_64+0x13e/0x147

-> #0 (console_owner){-...}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3158 [inline]
       check_prevs_add kernel/locking/lockdep.c:3277 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3901
       __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
       console_trylock_spinning kernel/printk/printk.c:2029 [inline]
       vprintk_emit+0x54d/0xa10 kernel/printk/printk.c:2406
       _printk+0xd5/0x120 kernel/printk/printk.c:2432
       fail_dump lib/fault-inject.c:45 [inline]
       should_fail_ex+0x391/0x4e0 lib/fault-inject.c:153
       strncpy_from_user+0x36/0x2e0 lib/strncpy_from_user.c:118
       strncpy_from_user_nofault+0x71/0x140 mm/maccess.c:186
       bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
       ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
       bpf_probe_read_compat_str+0xe9/0x180 kernel/trace/bpf_trace.c:307
       bpf_prog_e42f6260c1b72fb3+0x3d/0x3f
       bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
       __bpf_prog_run include/linux/filter.h:691 [inline]
       bpf_prog_run include/linux/filter.h:698 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
       bpf_trace_run4+0x334/0x590 kernel/trace/bpf_trace.c:2449
       __traceiter_sched_switch+0x98/0xd0 include/trace/events/sched.h:222
       trace_sched_switch include/trace/events/sched.h:222 [inline]
       __schedule+0x22f8/0x4b00 kernel/sched/core.c:6604
       preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6929
       irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
       asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
       syscall_enter_from_user_mode_work include/linux/entry-common.h:165 [inline]
       syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
       do_syscall_64+0xbc/0x230 arch/x86/entry/common.c:79
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  console_owner --> &p->pi_lock --> &rq->__lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&rq->__lock);
                               lock(&p->pi_lock);
                               lock(&rq->__lock);
  lock(console_owner);

 *** DEADLOCK ***

2 locks held by syz.2.116/5789:
 #0: ffff8880b883e958 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:585
 #1: ffffffff8e9389e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #1: ffffffff8e9389e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffffff8e9389e0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2405 [inline]
 #1: ffffffff8e9389e0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x244/0x590 kernel/trace/bpf_trace.c:2449

stack backtrace:
CPU: 0 UID: 0 PID: 5789 Comm: syz.2.116 Not tainted 6.11.0-syzkaller-07337-g2004cef11ea0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2203
 check_prev_add kernel/locking/lockdep.c:3158 [inline]
 check_prevs_add kernel/locking/lockdep.c:3277 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3901
 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
 console_trylock_spinning kernel/printk/printk.c:2029 [inline]
 vprintk_emit+0x54d/0xa10 kernel/printk/printk.c:2406
 _printk+0xd5/0x120 kernel/printk/printk.c:2432
 fail_dump lib/fault-inject.c:45 [inline]
 should_fail_ex+0x391/0x4e0 lib/fault-inject.c:153
 strncpy_from_user+0x36/0x2e0 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x71/0x140 mm/maccess.c:186
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
 ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
 bpf_probe_read_compat_str+0xe9/0x180 kernel/trace/bpf_trace.c:307
 bpf_prog_e42f6260c1b72fb3+0x3d/0x3f
 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
 __bpf_prog_run include/linux/filter.h:691 [inline]
 bpf_prog_run include/linux/filter.h:698 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
 bpf_trace_run4+0x334/0x590 kernel/trace/bpf_trace.c:2449
 __traceiter_sched_switch+0x98/0xd0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x22f8/0x4b00 kernel/sched/core.c:6604
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6929
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:syscall_enter_from_user_mode_work include/linux/entry-common.h:167 [inline]
RIP: 0010:syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
RIP: 0010:do_syscall_64+0xbc/0x230 arch/x86/entry/common.c:79
Code: ed 00 00 00 48 8b 7d 08 e8 c1 64 00 00 0f 1f 44 00 00 0f 1f 44 00 00 90 e8 91 fc e5 f5 90 90 e8 3a fc e5 f5 fb 49 8b 54 24 08 <f6> c2 3f 74 0e 4c 89 f7 4c 89 fe e8 a4 5a c8 f5 49 89 c7 90 90 41
RSP: 0018:ffffc9000935ff10 EFLAGS: 00000282
RAX: 63f8402ddfeeb000 RBX: ffffc9000935ff10 RCX: ffffffff9a370903
RDX: 0000000000000000 RSI: ffffffff8c0ad7c0 RDI: ffffffff8c600900
RBP: ffffc9000935ff48 R08: ffffffff901b2eaf R09: 1ffffffff20365d5
R10: dffffc0000000000 R11: fffffbfff20365d6 R12: ffff88802537bc00
R13: 0000000000000000 R14: ffffc9000935ff58 R15: 0000000000000000
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f224397c93c
Code: ec 28 48 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 69 8e 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 34 44 89 c7 48 89 44 24 08 e8 bf 8e 02 00 48
RSP: 002b:00007f22446fd030 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f2243b36058 RCX: 00007f224397c93c
RDX: 000000000000000f RSI: 00007f22446fd0a0 RDI: 0000000000000005
RBP: 00007f22446fd090 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000200004c0 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 00007f2243b36058 R15: 00007fffd12e7e28
 </TASK>
CPU: 0 UID: 0 PID: 5789 Comm: syz.2.116 Not tainted 6.11.0-syzkaller-07337-g2004cef11ea0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail_ex+0x3b0/0x4e0 lib/fault-inject.c:153
 strncpy_from_user+0x36/0x2e0 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x71/0x140 mm/maccess.c:186
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
 ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
 bpf_probe_read_compat_str+0xe9/0x180 kernel/trace/bpf_trace.c:307
 bpf_prog_e42f6260c1b72fb3+0x3d/0x3f
 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
 __bpf_prog_run include/linux/filter.h:691 [inline]
 bpf_prog_run include/linux/filter.h:698 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
 bpf_trace_run4+0x334/0x590 kernel/trace/bpf_trace.c:2449
 __traceiter_sched_switch+0x98/0xd0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x22f8/0x4b00 kernel/sched/core.c:6604
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6929
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:syscall_enter_from_user_mode_work include/linux/entry-common.h:167 [inline]
RIP: 0010:syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
RIP: 0010:do_syscall_64+0xbc/0x230 arch/x86/entry/common.c:79
Code: ed 00 00 00 48 8b 7d 08 e8 c1 64 00 00 0f 1f 44 00 00 0f 1f 44 00 00 90 e8 91 fc e5 f5 90 90 e8 3a fc e5 f5 fb 49 8b 54 24 08 <f6> c2 3f 74 0e 4c 89 f7 4c 89 fe e8 a4 5a c8 f5 49 89 c7 90 90 41
RSP: 0018:ffffc9000935ff10 EFLAGS: 00000282
RAX: 63f8402ddfeeb000 RBX: ffffc9000935ff10 RCX: ffffffff9a370903
RDX: 0000000000000000 RSI: ffffffff8c0ad7c0 RDI: ffffffff8c600900
RBP: ffffc9000935ff48 R08: ffffffff901b2eaf R09: 1ffffffff20365d5
R10: dffffc0000000000 R11: fffffbfff20365d6 R12: ffff88802537bc00
R13: 0000000000000000 R14: ffffc9000935ff58 R15: 0000000000000000
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f224397c93c
Code: ec 28 48 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 69 8e 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 34 44 89 c7 48 89 44 24 08 e8 bf 8e 02 00 48
RSP: 002b:00007f22446fd030 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f2243b36058 RCX: 00007f224397c93c
RDX: 000000000000000f RSI: 00007f22446fd0a0 RDI: 0000000000000005
RBP: 00007f22446fd090 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000200004c0 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 00007f2243b36058 R15: 00007fffd12e7e28
 </TASK>
----------------
Code disassembly (best guess):
   0:	ed                   	in     (%dx),%eax
   1:	00 00                	add    %al,(%rax)
   3:	00 48 8b             	add    %cl,-0x75(%rax)
   6:	7d 08                	jge    0x10
   8:	e8 c1 64 00 00       	call   0x64ce
   d:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  12:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  17:	90                   	nop
  18:	e8 91 fc e5 f5       	call   0xf5e5fcae
  1d:	90                   	nop
  1e:	90                   	nop
  1f:	e8 3a fc e5 f5       	call   0xf5e5fc5e
  24:	fb                   	sti
  25:	49 8b 54 24 08       	mov    0x8(%r12),%rdx
* 2a:	f6 c2 3f             	test   $0x3f,%dl <-- trapping instruction
  2d:	74 0e                	je     0x3d
  2f:	4c 89 f7             	mov    %r14,%rdi
  32:	4c 89 fe             	mov    %r15,%rsi
  35:	e8 a4 5a c8 f5       	call   0xf5c85ade
  3a:	49 89 c7             	mov    %rax,%r15
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	41                   	rex.B