FAULT_INJECTION: forcing a failure. name fail_usercopy, interval 1, probability 0, space 0, times 0 ====================================================== WARNING: possible circular locking dependency detected 6.16.0-syzkaller-06699-ge8d780dcd957 #0 Not tainted ------------------------------------------------------ syz.2.2015/13845 is trying to acquire lock: ffffffff8e4d1060 (console_owner){-.-.}-{0:0}, at: console_lock_spinning_enable+0x9f/0xd0 kernel/printk/printk.c:1924 but task is already holding lock: ffff8880b843a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:644 [inline] ffff8880b843a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:629 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:636 raw_spin_rq_lock kernel/sched/sched.h:1522 [inline] task_rq_lock+0xcf/0x490 kernel/sched/core.c:736 cgroup_move_task+0x81/0x2a0 kernel/sched/psi.c:1174 css_set_move_task+0x288/0x5f0 kernel/cgroup/cgroup.c:918 cgroup_post_fork+0x201/0x9e0 kernel/cgroup/cgroup.c:6759 copy_process+0x5cfa/0x7690 kernel/fork.c:2416 kernel_clone+0xfc/0x930 kernel/fork.c:2602 user_mode_thread+0xc7/0x110 kernel/fork.c:2680 rest_init+0x23/0x2b0 init/main.c:709 start_kernel+0x3ee/0x4d0 init/main.c:1097 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x148 -> #3 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline] try_to_wake_up+0xb2/0x1680 kernel/sched/core.c:4210 __wake_up_common+0x135/0x1f0 kernel/sched/wait.c:90 __wake_up_common_lock kernel/sched/wait.c:107 [inline] __wake_up+0x31/0x60 kernel/sched/wait.c:128 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1728 serial8250_handle_irq+0x761/0xcb0 drivers/tty/serial/8250/8250_port.c:1836 serial8250_default_handle_irq+0x9a/0x250 drivers/tty/serial/8250/8250_port.c:1856 serial8250_interrupt+0xf8/0x1b0 drivers/tty/serial/8250/8250_core.c:82 __handle_irq_event_percpu+0x229/0x7d0 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x3b3/0x9d0 kernel/irq/chip.c:849 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:254 [inline] call_irq_handler arch/x86/kernel/irq.c:266 [inline] __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:292 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:285 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:81 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 -> #2 (&tty->write_wait){-.-.}-{3:3}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 __wake_up_common_lock kernel/sched/wait.c:106 [inline] __wake_up+0x1c/0x60 kernel/sched/wait.c:128 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1728 serial8250_handle_irq+0x761/0xcb0 drivers/tty/serial/8250/8250_port.c:1836 serial8250_default_handle_irq+0x9a/0x250 drivers/tty/serial/8250/8250_port.c:1856 serial8250_interrupt+0xf8/0x1b0 drivers/tty/serial/8250/8250_core.c:82 __handle_irq_event_percpu+0x229/0x7d0 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x3b3/0x9d0 kernel/irq/chip.c:849 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:254 [inline] call_irq_handler arch/x86/kernel/irq.c:266 [inline] __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:292 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:285 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:81 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 -> #1 (&port_lock_key){-.-.}-{3:3}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:717 [inline] serial8250_console_write+0x181/0x1890 drivers/tty/serial/8250/8250_port.c:3355 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x801/0xc60 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 _printk+0xc7/0x100 kernel/printk/printk.c:2475 register_console+0xc2d/0x11b0 kernel/printk/printk.c:4125 univ8250_console_init+0x5f/0x90 drivers/tty/serial/8250/8250_core.c:516 console_init+0x14f/0x680 kernel/printk/printk.c:4323 start_kernel+0x29f/0x4d0 init/main.c:1035 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x148 -> #0 (console_owner){-.-.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x126f/0x1c90 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 console_lock_spinning_enable+0xb0/0xd0 kernel/printk/printk.c:1924 console_emit_next_record kernel/printk/printk.c:3132 [inline] console_flush_all+0x7aa/0xc60 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 _printk+0xc7/0x100 kernel/printk/printk.c:2475 fail_dump lib/fault-inject.c:66 [inline] should_fail_ex+0x4e7/0x640 lib/fault-inject.c:174 strncpy_from_user+0x3b/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:193 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:215 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:224 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:221 bpf_prog_bc7c5c6b9645592f+0x3e/0x44 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline] bpf_trace_run4+0x24f/0x5b0 kernel/trace/bpf_trace.c:2300 __bpf_trace_sched_switch+0x145/0x190 include/trace/events/sched.h:220 __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:220 __do_trace_sched_switch include/trace/events/sched.h:220 [inline] trace_sched_switch include/trace/events/sched.h:220 [inline] __schedule+0x1845/0x5df0 kernel/sched/core.c:6951 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7281 irqentry_exit+0x36/0x90 kernel/entry/common.c:196 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 rcu_preempt_read_enter kernel/rcu/tree_plugin.h:391 [inline] __rcu_read_lock+0x37/0xf0 kernel/rcu/tree_plugin.h:414 rcu_read_lock include/linux/rcupdate.h:839 [inline] __fget_files+0x22/0x3c0 fs/file.c:1070 __fget_light fs/file.c:1173 [inline] fdget+0x1a9/0x210 fs/file.c:1181 class_fd_constructor include/linux/file.h:83 [inline] __sys_sendmsg+0xc9/0x220 net/socket.c:2692 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 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 *** 4 locks held by syz.2.2015/13845: #0: ffff8880b843a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:644 [inline] #0: ffff8880b843a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:629 #1: ffffffff8e5c3a20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #1: ffffffff8e5c3a20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #1: ffffffff8e5c3a20 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2256 [inline] #1: ffffffff8e5c3a20 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run4+0x1d5/0x5b0 kernel/trace/bpf_trace.c:2300 #2: ffffffff8e5b14a0 (console_lock){+.+.}-{0:0}, at: _printk+0xc7/0x100 kernel/printk/printk.c:2475 #3: ffffffff8e5b1510 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:336 [inline] #3: ffffffff8e5b1510 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:319 [inline] #3: ffffffff8e5b1510 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:288 [inline] #3: ffffffff8e5b1510 (console_srcu){....}-{0:0}, at: console_flush_all+0x158/0xc60 kernel/printk/printk.c:3203 stack backtrace: CPU: 0 UID: 0 PID: 13845 Comm: syz.2.2015 Not tainted 6.16.0-syzkaller-06699-ge8d780dcd957 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x275/0x350 kernel/locking/lockdep.c:2043 check_noncircular+0x14c/0x170 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x126f/0x1c90 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 console_lock_spinning_enable+0xb0/0xd0 kernel/printk/printk.c:1924 console_emit_next_record kernel/printk/printk.c:3132 [inline] console_flush_all+0x7aa/0xc60 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 _printk+0xc7/0x100 kernel/printk/printk.c:2475 fail_dump lib/fault-inject.c:66 [inline] should_fail_ex+0x4e7/0x640 lib/fault-inject.c:174 strncpy_from_user+0x3b/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:193 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:215 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:224 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:221 bpf_prog_bc7c5c6b9645592f+0x3e/0x44 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline] bpf_trace_run4+0x24f/0x5b0 kernel/trace/bpf_trace.c:2300 __bpf_trace_sched_switch+0x145/0x190 include/trace/events/sched.h:220 __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:220 __do_trace_sched_switch include/trace/events/sched.h:220 [inline] trace_sched_switch include/trace/events/sched.h:220 [inline] __schedule+0x1845/0x5df0 kernel/sched/core.c:6951 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7281 irqentry_exit+0x36/0x90 kernel/entry/common.c:196 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:rcu_preempt_read_enter kernel/rcu/tree_plugin.h:391 [inline] RIP: 0010:__rcu_read_lock+0x37/0xf0 kernel/rcu/tree_plugin.h:414 Code: df 55 53 65 48 8b 1d 70 7b 2f 12 48 8d bb 44 04 00 00 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 <84> d2 0f 85 a6 00 00 00 65 48 8b 2d 41 7b 2f 12 48 8d bd 44 04 00 RSP: 0018:ffffc90004bafd68 EFLAGS: 00000202 RAX: 0000000000000007 RBX: ffff88802a5c0000 RCX: ffffffff823cca97 RDX: 0000000000000000 RSI: ffffffff823cc59d RDI: ffff88802a5c0444 RBP: 0000000000000004 R08: 0000000000000005 R09: 0000000000000001 R10: 0000000000000003 R11: 0000000000000000 R12: ffff888021f15a40 R13: 0000000000000004 R14: 0000000000000001 R15: ffffc90004bafe40 rcu_read_lock include/linux/rcupdate.h:839 [inline] __fget_files+0x22/0x3c0 fs/file.c:1070 __fget_light fs/file.c:1173 [inline] fdget+0x1a9/0x210 fs/file.c:1181 class_fd_constructor include/linux/file.h:83 [inline] __sys_sendmsg+0xc9/0x220 net/socket.c:2692 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f87f318e9a9 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:00007f87f0ff6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f87f33b6080 RCX: 00007f87f318e9a9 RDX: 0000000000000810 RSI: 0000200000000000 RDI: 0000000000000004 RBP: 00007f87f0ff6090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f87f33b6080 R15: 00007ffd8dde25e8 CPU: 0 UID: 0 PID: 13845 Comm: syz.2.2015 Not tainted 6.16.0-syzkaller-06699-ge8d780dcd957 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 fail_dump lib/fault-inject.c:73 [inline] should_fail_ex+0x512/0x640 lib/fault-inject.c:174 strncpy_from_user+0x3b/0x2e0 lib/strncpy_from_user.c:118 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:193 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:215 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:224 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:221 bpf_prog_bc7c5c6b9645592f+0x3e/0x44 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline] bpf_trace_run4+0x24f/0x5b0 kernel/trace/bpf_trace.c:2300 __bpf_trace_sched_switch+0x145/0x190 include/trace/events/sched.h:220 __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:220 __do_trace_sched_switch include/trace/events/sched.h:220 [inline] trace_sched_switch include/trace/events/sched.h:220 [inline] __schedule+0x1845/0x5df0 kernel/sched/core.c:6951 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7281 irqentry_exit+0x36/0x90 kernel/entry/common.c:196 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:rcu_preempt_read_enter kernel/rcu/tree_plugin.h:391 [inline] RIP: 0010:__rcu_read_lock+0x37/0xf0 kernel/rcu/tree_plugin.h:414 Code: df 55 53 65 48 8b 1d 70 7b 2f 12 48 8d bb 44 04 00 00 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 <84> d2 0f 85 a6 00 00 00 65 48 8b 2d 41 7b 2f 12 48 8d bd 44 04 00 RSP: 0018:ffffc90004bafd68 EFLAGS: 00000202 RAX: 0000000000000007 RBX: ffff88802a5c0000 RCX: ffffffff823cca97 RDX: 0000000000000000 RSI: ffffffff823cc59d RDI: ffff88802a5c0444 RBP: 0000000000000004 R08: 0000000000000005 R09: 0000000000000001 R10: 0000000000000003 R11: 0000000000000000 R12: ffff888021f15a40 R13: 0000000000000004 R14: 0000000000000001 R15: ffffc90004bafe40 rcu_read_lock include/linux/rcupdate.h:839 [inline] __fget_files+0x22/0x3c0 fs/file.c:1070 __fget_light fs/file.c:1173 [inline] fdget+0x1a9/0x210 fs/file.c:1181 class_fd_constructor include/linux/file.h:83 [inline] __sys_sendmsg+0xc9/0x220 net/socket.c:2692 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f87f318e9a9 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:00007f87f0ff6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f87f33b6080 RCX: 00007f87f318e9a9 RDX: 0000000000000810 RSI: 0000200000000000 RDI: 0000000000000004 RBP: 00007f87f0ff6090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f87f33b6080 R15: 00007ffd8dde25e8 ---------------- Code disassembly (best guess): 0: df 55 53 fists 0x53(%rbp) 3: 65 48 8b 1d 70 7b 2f mov %gs:0x122f7b70(%rip),%rbx # 0x122f7b7b a: 12 b: 48 8d bb 44 04 00 00 lea 0x444(%rbx),%rdi 12: 48 89 fa mov %rdi,%rdx 15: 48 c1 ea 03 shr $0x3,%rdx 19: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx 1d: 48 89 f8 mov %rdi,%rax 20: 83 e0 07 and $0x7,%eax 23: 83 c0 03 add $0x3,%eax 26: 38 d0 cmp %dl,%al 28: 7c 08 jl 0x32 * 2a: 84 d2 test %dl,%dl <-- trapping instruction 2c: 0f 85 a6 00 00 00 jne 0xd8 32: 65 48 8b 2d 41 7b 2f mov %gs:0x122f7b41(%rip),%rbp # 0x122f7b7b 39: 12 3a: 48 rex.W 3b: 8d .byte 0x8d 3c: bd .byte 0xbd 3d: 44 04 00 rex.R add $0x0,%al