FAULT_INJECTION: forcing a failure. name fail_usercopy, interval 1, probability 0, space 0, times 0 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.5.1716/13337 is trying to acquire lock: ffffffff8e2d6bc0 (console_owner){-.-.}-{0:0}, at: console_lock_spinning_enable+0x61/0x80 kernel/printk/printk.c:1900 but task is already holding lock: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline] ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632 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:639 raw_spin_rq_lock kernel/sched/sched.h:1580 [inline] task_rq_lock+0xcf/0x490 kernel/sched/core.c:739 cgroup_move_task+0x81/0x2a0 kernel/sched/psi.c:1170 css_set_move_task+0x288/0x5f0 kernel/cgroup/cgroup.c:948 cgroup_post_fork+0x201/0x9e0 kernel/cgroup/cgroup.c:6910 copy_process+0x56b6/0x7430 kernel/fork.c:2465 kernel_clone+0xfc/0x910 kernel/fork.c:2651 user_mode_thread+0xc8/0x110 kernel/fork.c:2727 rest_init+0x23/0x2b0 init/main.c:722 start_kernel+0x3ef/0x4d0 init/main.c:1206 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291 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+0xb7/0x1860 kernel/sched/core.c:4106 __wake_up_common+0x135/0x1f0 kernel/sched/wait.c:108 __wake_up_common_lock kernel/sched/wait.c:125 [inline] __wake_up+0x31/0x60 kernel/sched/wait.c:146 tty_ldisc_lock+0x59/0xb0 drivers/tty/tty_ldisc.c:311 tty_set_ldisc+0x98/0x780 drivers/tty/tty_ldisc.c:529 tiocsetd drivers/tty/tty_io.c:2429 [inline] tty_ioctl+0xc2d/0x1650 drivers/tty/tty_io.c:2728 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #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:124 [inline] __wake_up+0x1c/0x60 kernel/sched/wait.c:146 tty_port_default_wakeup+0x4d/0x60 drivers/tty/tty_port.c:67 serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1719 serial8250_handle_irq+0x761/0xcb0 drivers/tty/serial/8250/8250_port.c:1827 serial8250_default_handle_irq+0x9e/0x270 drivers/tty/serial/8250/8250_port.c:1846 serial8250_interrupt+0xf8/0x1d0 drivers/tty/serial/8250/8250_core.c:86 __handle_irq_event_percpu+0x236/0x890 kernel/irq/handle.c:211 handle_irq_event_percpu kernel/irq/handle.c:248 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:265 handle_edge_irq+0x3ca/0x9e0 kernel/irq/chip.c:855 generic_handle_irq_desc include/linux/irqdesc.h:172 [inline] handle_irq arch/x86/kernel/irq.c:255 [inline] call_irq_handler arch/x86/kernel/irq.c:311 [inline] __common_interrupt+0xd0/0x2f0 arch/x86/kernel/irq.c:326 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:319 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688 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:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x38d/0x510 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 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:3301 console_emit_next_record kernel/printk/printk.c:3129 [inline] console_flush_one_record+0x796/0xc60 kernel/printk/printk.c:3215 console_flush_all kernel/printk/printk.c:3289 [inline] __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xef/0x240 kernel/printk/printk.c:3359 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426 _printk+0xc7/0x100 kernel/printk/printk.c:2451 register_console+0x823/0x1210 kernel/printk/printk.c:4170 univ8250_console_init+0x5f/0x90 drivers/tty/serial/8250/8250_core.c:515 console_init+0x152/0x600 kernel/printk/printk.c:4369 start_kernel+0x298/0x4d0 init/main.c:1143 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291 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+0x1669/0x2890 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 kernel/locking/lockdep.c:5825 console_lock_spinning_enable+0x72/0x80 kernel/printk/printk.c:1900 console_emit_next_record kernel/printk/printk.c:3123 [inline] console_flush_one_record+0x73f/0xc60 kernel/printk/printk.c:3215 console_flush_all kernel/printk/printk.c:3289 [inline] __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xef/0x240 kernel/printk/printk.c:3359 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426 _printk+0xc7/0x100 kernel/printk/printk.c:2451 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:192 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:214 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:223 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:220 bpf_prog_c762caf419d1c004+0x3e/0x44 bpf_dispatcher_nop_func include/linux/bpf.h:1378 [inline] __bpf_prog_run include/linux/filter.h:723 [inline] bpf_prog_run include/linux/filter.h:730 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline] bpf_trace_run4+0x252/0x5e0 kernel/trace/bpf_trace.c:2118 __bpf_trace_sched_switch+0x145/0x190 include/trace/events/sched.h:220 __traceiter_sched_switch+0x6f/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+0x1a1b/0x5ee0 kernel/sched/core.c:6864 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7194 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 __sanitizer_cov_trace_pc+0x4/0x70 kernel/kcov.c:210 scm_send include/net/scm.h:94 [inline] netlink_sendmsg+0x15a/0xdd0 net/netlink/af_netlink.c:1832 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2646 __sys_sendmsg+0x16d/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 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.5.1716/13337: #0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline] #0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632 #1: ffffffff8e3c9620 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #1: ffffffff8e3c9620 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #1: ffffffff8e3c9620 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2074 [inline] #1: ffffffff8e3c9620 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run4+0x1d5/0x5e0 kernel/trace/bpf_trace.c:2118 #2: ffffffff8e3b7000 (console_lock){+.+.}-{0:0}, at: _printk+0xc7/0x100 kernel/printk/printk.c:2451 #3: ffffffff8e3b7078 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:336 [inline] #3: ffffffff8e3b7078 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:409 [inline] #3: ffffffff8e3b7078 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:289 [inline] #3: ffffffff8e3b7078 (console_srcu){....}-{0:0}, at: console_flush_one_record+0x103/0xc60 kernel/printk/printk.c:3192 stack backtrace: CPU: 1 UID: 0 PID: 13337 Comm: syz.5.1716 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x275/0x340 kernel/locking/lockdep.c:2043 check_noncircular+0x146/0x160 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+0x1669/0x2890 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 kernel/locking/lockdep.c:5825 console_lock_spinning_enable+0x72/0x80 kernel/printk/printk.c:1900 console_emit_next_record kernel/printk/printk.c:3123 [inline] console_flush_one_record+0x73f/0xc60 kernel/printk/printk.c:3215 console_flush_all kernel/printk/printk.c:3289 [inline] __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xef/0x240 kernel/printk/printk.c:3359 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426 _printk+0xc7/0x100 kernel/printk/printk.c:2451 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:192 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:214 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:223 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:220 bpf_prog_c762caf419d1c004+0x3e/0x44 bpf_dispatcher_nop_func include/linux/bpf.h:1378 [inline] __bpf_prog_run include/linux/filter.h:723 [inline] bpf_prog_run include/linux/filter.h:730 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline] bpf_trace_run4+0x252/0x5e0 kernel/trace/bpf_trace.c:2118 __bpf_trace_sched_switch+0x145/0x190 include/trace/events/sched.h:220 __traceiter_sched_switch+0x6f/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+0x1a1b/0x5ee0 kernel/sched/core.c:6864 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7194 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x70 kernel/kcov.c:213 Code: 48 89 df 5b e9 fd 1c 5e 00 be 03 00 00 00 5b e9 e2 11 ee 02 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <48> 8b 34 24 65 48 8b 15 78 f0 f3 11 65 8b 05 89 f0 f3 11 a9 00 01 RSP: 0018:ffffc900053079f0 EFLAGS: 00000206 RAX: 0000000000000000 RBX: ffffc90005307e30 RCX: ffffffff8988c40c RDX: ffff88802c564980 RSI: 0000000000000000 RDI: 0000000000000007 RBP: ffffc90005307a58 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000014 R11: 0000000000000001 R12: 0000000000000014 R13: 0000000000000000 R14: 0000000000000014 R15: ffff8880554c3000 scm_send include/net/scm.h:94 [inline] netlink_sendmsg+0x15a/0xdd0 net/netlink/af_netlink.c:1832 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2646 __sys_sendmsg+0x16d/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f457fb8f749 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:00007f45809f1038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f457fde6090 RCX: 00007f457fb8f749 RDX: 0000000000000000 RSI: 0000200000001240 RDI: 0000000000000004 RBP: 00007f45809f1090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f457fde6128 R14: 00007f457fde6090 R15: 00007ffd054c1fe8 CPU: 1 UID: 0 PID: 13337 Comm: syz.5.1716 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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:192 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:214 [inline] ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:223 [inline] bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:220 bpf_prog_c762caf419d1c004+0x3e/0x44 bpf_dispatcher_nop_func include/linux/bpf.h:1378 [inline] __bpf_prog_run include/linux/filter.h:723 [inline] bpf_prog_run include/linux/filter.h:730 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline] bpf_trace_run4+0x252/0x5e0 kernel/trace/bpf_trace.c:2118 __bpf_trace_sched_switch+0x145/0x190 include/trace/events/sched.h:220 __traceiter_sched_switch+0x6f/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+0x1a1b/0x5ee0 kernel/sched/core.c:6864 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7194 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x70 kernel/kcov.c:213 Code: 48 89 df 5b e9 fd 1c 5e 00 be 03 00 00 00 5b e9 e2 11 ee 02 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <48> 8b 34 24 65 48 8b 15 78 f0 f3 11 65 8b 05 89 f0 f3 11 a9 00 01 RSP: 0018:ffffc900053079f0 EFLAGS: 00000206 RAX: 0000000000000000 RBX: ffffc90005307e30 RCX: ffffffff8988c40c RDX: ffff88802c564980 RSI: 0000000000000000 RDI: 0000000000000007 RBP: ffffc90005307a58 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000014 R11: 0000000000000001 R12: 0000000000000014 R13: 0000000000000000 R14: 0000000000000014 R15: ffff8880554c3000 scm_send include/net/scm.h:94 [inline] netlink_sendmsg+0x15a/0xdd0 net/netlink/af_netlink.c:1832 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2646 __sys_sendmsg+0x16d/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f457fb8f749 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:00007f45809f1038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f457fde6090 RCX: 00007f457fb8f749 RDX: 0000000000000000 RSI: 0000200000001240 RDI: 0000000000000004 RBP: 00007f45809f1090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f457fde6128 R14: 00007f457fde6090 R15: 00007ffd054c1fe8 ---------------- Code disassembly (best guess): 0: 48 89 df mov %rbx,%rdi 3: 5b pop %rbx 4: e9 fd 1c 5e 00 jmp 0x5e1d06 9: be 03 00 00 00 mov $0x3,%esi e: 5b pop %rbx f: e9 e2 11 ee 02 jmp 0x2ee11f6 14: 66 90 xchg %ax,%ax 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 90 nop 25: 90 nop 26: f3 0f 1e fa endbr64 * 2a: 48 8b 34 24 mov (%rsp),%rsi <-- trapping instruction 2e: 65 48 8b 15 78 f0 f3 mov %gs:0x11f3f078(%rip),%rdx # 0x11f3f0ae 35: 11 36: 65 8b 05 89 f0 f3 11 mov %gs:0x11f3f089(%rip),%eax # 0x11f3f0c6 3d: a9 .byte 0xa9 3e: 00 01 add %al,(%rcx)