------------[ cut here ]------------
======================================================
WARNING: possible circular locking dependency detected
6.7.0-rc4-next-20231205-syzkaller #0 Not tainted
------------------------------------------------------
swapper/1/0 is trying to acquire lock:
ffffffff8d19a0f8 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
but task is already holding lock:
ffffffff8dc76638 (pool_rwlock){----}-{2:2}, at: stack_depot_put lib/stackdepot.c:621 [inline]
ffffffff8dc76638 (pool_rwlock){----}-{2:2}, at: stack_depot_put+0x24/0x110 lib/stackdepot.c:613
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (pool_rwlock){----}-{2:2}:
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0x46/0x90 kernel/locking/spinlock.c:236
stack_depot_save_flags+0x169/0x740 lib/stackdepot.c:508
kasan_save_stack+0x42/0x50 mm/kasan/common.c:48
__kasan_record_aux_stack+0xc2/0xd0 mm/kasan/generic.c:517
task_work_add+0x88/0x2a0 kernel/task_work.c:48
task_tick_numa kernel/sched/fair.c:3512 [inline]
task_tick_fair+0x5a5/0xc30 kernel/sched/fair.c:12599
scheduler_tick+0x210/0x650 kernel/sched/core.c:5674
update_process_times+0x19e/0x220 kernel/time/timer.c:2076
tick_sched_handle+0x8e/0x170 kernel/time/tick-sched.c:255
tick_nohz_highres_handler+0xe9/0x110 kernel/time/tick-sched.c:1516
__run_hrtimer kernel/time/hrtimer.c:1688 [inline]
__hrtimer_run_queues+0x654/0xc20 kernel/time/hrtimer.c:1752
hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline]
__sysvec_apic_timer_interrupt+0x10c/0x410 arch/x86/kernel/apic/apic.c:1082
sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1076
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
__raw_read_unlock_irqrestore include/linux/rwlock_api_smp.h:241 [inline]
_raw_read_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:268
stack_depot_save_flags+0x2a1/0x740 lib/stackdepot.c:523
save_stack+0x16b/0x1f0 mm/page_owner.c:131
__set_page_owner+0x1f/0x60 mm/page_owner.c:196
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1540
prep_new_page mm/page_alloc.c:1547 [inline]
get_page_from_freelist+0xa19/0x3740 mm/page_alloc.c:3355
__alloc_pages+0x22e/0x2410 mm/page_alloc.c:4611
alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133
alloc_slab_page mm/slub.c:2158 [inline]
allocate_slab mm/slub.c:2325 [inline]
new_slab+0x283/0x3c0 mm/slub.c:2378
___slab_alloc+0x4ab/0x1990 mm/slub.c:3511
__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3596
__slab_alloc_node mm/slub.c:3649 [inline]
slab_alloc_node mm/slub.c:3821 [inline]
kmem_cache_alloc+0x2e9/0x320 mm/slub.c:3838
vm_area_alloc+0x1f/0x220 kernel/fork.c:463
mmap_region+0x3ae/0x2a90 mm/mmap.c:2801
do_mmap+0x890/0xef0 mm/mmap.c:1379
vm_mmap_pgoff+0x1a7/0x3c0 mm/util.c:556
vm_mmap+0x8e/0xc0 mm/util.c:575
elf_map fs/binfmt_elf.c:381 [inline]
elf_load+0x3da/0x870 fs/binfmt_elf.c:408
load_elf_interp fs/binfmt_elf.c:675 [inline]
load_elf_binary+0x3436/0x4e10 fs/binfmt_elf.c:1200
search_binary_handler fs/exec.c:1736 [inline]
exec_binprm fs/exec.c:1778 [inline]
bprm_execve fs/exec.c:1853 [inline]
bprm_execve+0x7ef/0x1a80 fs/exec.c:1809
kernel_execve+0x3d7/0x4e0 fs/exec.c:2021
try_to_run_init_process init/main.c:1364 [inline]
kernel_init+0x137/0x2a0 init/main.c:1497
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
-> #2 (&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:558
raw_spin_rq_lock kernel/sched/sched.h:1385 [inline]
rq_lock kernel/sched/sched.h:1699 [inline]
task_fork_fair+0x70/0x240 kernel/sched/fair.c:12619
sched_cgroup_fork+0x3cf/0x510 kernel/sched/core.c:4835
copy_process+0x6a38/0x9770 kernel/fork.c:2601
kernel_clone+0xfd/0x940 kernel/fork.c:2899
user_mode_thread+0xb4/0xf0 kernel/fork.c:2977
rest_init+0x27/0x2b0 init/main.c:695
arch_call_rest_init+0x13/0x30 init/main.c:827
start_kernel+0x39e/0x480 init/main.c:1072
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:555
x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:536
secondary_startup_64_no_verify+0x166/0x16b
-> #1 (&p->pi_lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162
class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:522 [inline]
try_to_wake_up+0x9a/0x13d0 kernel/sched/core.c:4252
up+0x79/0xb0 kernel/locking/semaphore.c:191
__up_console_sem kernel/printk/printk.c:340 [inline]
__console_unlock kernel/printk/printk.c:2706 [inline]
console_unlock+0x1cf/0x260 kernel/printk/printk.c:3038
vprintk_emit+0x17f/0x5f0 kernel/printk/printk.c:2303
vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45
_printk+0xc8/0x100 kernel/printk/printk.c:2328
kauditd_printk_skb kernel/audit.c:546 [inline]
kauditd_hold_skb+0x1fb/0x240 kernel/audit.c:581
kauditd_send_queue+0x229/0x280 kernel/audit.c:766
kauditd_thread+0x61e/0xa80 kernel/audit.c:890
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
-> #0 ((console_sem).lock){-.-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x246e/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5719
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162
down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
__down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:323
console_trylock+0x73/0x130 kernel/printk/printk.c:2659
console_trylock_spinning kernel/printk/printk.c:1923 [inline]
vprintk_emit+0x162/0x5f0 kernel/printk/printk.c:2302
vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45
_printk+0xc8/0x100 kernel/printk/printk.c:2328
__warn_printk+0x158/0x350 kernel/panic.c:721
refcount_warn_saturate+0x149/0x210 lib/refcount.c:28
__refcount_sub_and_test include/linux/refcount.h:283 [inline]
__refcount_dec_and_test include/linux/refcount.h:315 [inline]
refcount_dec_and_test include/linux/refcount.h:333 [inline]
stack_depot_put lib/stackdepot.c:627 [inline]
stack_depot_put+0xe4/0x110 lib/stackdepot.c:613
__kasan_record_aux_stack+0xb3/0xd0 mm/kasan/generic.c:515
insert_work+0x38/0x230 kernel/workqueue.c:1653
__queue_work+0x633/0x11d0 kernel/workqueue.c:1802
__queue_delayed_work+0x1bf/0x270 kernel/workqueue.c:1953
mod_delayed_work_on+0xcc/0x1a0 kernel/workqueue.c:2027
kblockd_mod_delayed_work_on+0x29/0x40 block/blk-core.c:1046
blk_kick_flush block/blk-flush.c:348 [inline]
blk_flush_complete_seq+0xa66/0x10c0 block/blk-flush.c:213
mq_flush_data_end_io+0x2e3/0x580 block/blk-flush.c:376
__blk_mq_end_request+0x248/0x4f0 block/blk-mq.c:1046
scsi_end_request+0x444/0x9a0 drivers/scsi/scsi_lib.c:572
scsi_io_completion+0x178/0x14c0 drivers/scsi/scsi_lib.c:975
scsi_complete+0x124/0x250 drivers/scsi/scsi_lib.c:1437
blk_complete_reqs+0xb2/0xf0 block/blk-mq.c:1131
__do_softirq+0x216/0x8d5 kernel/softirq.c:553
invoke_softirq kernel/softirq.c:427 [inline]
__irq_exit_rcu kernel/softirq.c:632 [inline]
irq_exit_rcu+0xb5/0x120 kernel/softirq.c:644
common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:247
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:636
native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline]
acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112
acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707
cpuidle_enter_state+0x83/0x500 drivers/cpuidle/cpuidle.c:267
cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388
cpuidle_idle_call kernel/sched/idle.c:215 [inline]
do_idle+0x314/0x3f0 kernel/sched/idle.c:312
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:410
start_secondary+0x20e/0x2a0 arch/x86/kernel/smpboot.c:336
secondary_startup_64_no_verify+0x166/0x16b
other info that might help us debug this:
Chain exists of:
(console_sem).lock --> &rq->__lock --> pool_rwlock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(pool_rwlock);
lock(&rq->__lock);
lock(pool_rwlock);
lock((console_sem).lock);
*** DEADLOCK ***
4 locks held by swapper/1/0:
#0: ffff888019358318 (&fq->mq_flush_lock){..-.}-{2:2}, at: mq_flush_data_end_io+0x25c/0x580 block/blk-flush.c:369
#1: ffffffff8d1ac6a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline]
#1: ffffffff8d1ac6a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline]
#1: ffffffff8d1ac6a0 (rcu_read_lock){....}-{1:2}, at: __queue_work+0xf2/0x11d0 kernel/workqueue.c:1730
#2: ffff8880b993c2f8 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x39e/0x11d0 kernel/workqueue.c:1766
#3: ffffffff8dc76638 (pool_rwlock){----}-{2:2}, at: stack_depot_put lib/stackdepot.c:621 [inline]
#3: ffffffff8dc76638 (pool_rwlock){----}-{2:2}, at: stack_depot_put+0x24/0x110 lib/stackdepot.c:613
stack backtrace:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.7.0-rc4-next-20231205-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
check_noncircular+0x316/0x400 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x246e/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5719
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162
down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
__down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:323
console_trylock+0x73/0x130 kernel/printk/printk.c:2659
console_trylock_spinning kernel/printk/printk.c:1923 [inline]
vprintk_emit+0x162/0x5f0 kernel/printk/printk.c:2302
vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45
_printk+0xc8/0x100 kernel/printk/printk.c:2328
__warn_printk+0x158/0x350 kernel/panic.c:721
refcount_warn_saturate+0x149/0x210 lib/refcount.c:28
__refcount_sub_and_test include/linux/refcount.h:283 [inline]
__refcount_dec_and_test include/linux/refcount.h:315 [inline]
refcount_dec_and_test include/linux/refcount.h:333 [inline]
stack_depot_put lib/stackdepot.c:627 [inline]
stack_depot_put+0xe4/0x110 lib/stackdepot.c:613
__kasan_record_aux_stack+0xb3/0xd0 mm/kasan/generic.c:515
insert_work+0x38/0x230 kernel/workqueue.c:1653
__queue_work+0x633/0x11d0 kernel/workqueue.c:1802
__queue_delayed_work+0x1bf/0x270 kernel/workqueue.c:1953
mod_delayed_work_on+0xcc/0x1a0 kernel/workqueue.c:2027
kblockd_mod_delayed_work_on+0x29/0x40 block/blk-core.c:1046
blk_kick_flush block/blk-flush.c:348 [inline]
blk_flush_complete_seq+0xa66/0x10c0 block/blk-flush.c:213
mq_flush_data_end_io+0x2e3/0x580 block/blk-flush.c:376
__blk_mq_end_request+0x248/0x4f0 block/blk-mq.c:1046
scsi_end_request+0x444/0x9a0 drivers/scsi/scsi_lib.c:572
scsi_io_completion+0x178/0x14c0 drivers/scsi/scsi_lib.c:975
scsi_complete+0x124/0x250 drivers/scsi/scsi_lib.c:1437
blk_complete_reqs+0xb2/0xf0 block/blk-mq.c:1131
__do_softirq+0x216/0x8d5 kernel/softirq.c:553
invoke_softirq kernel/softirq.c:427 [inline]
__irq_exit_rcu kernel/softirq.c:632 [inline]
irq_exit_rcu+0xb5/0x120 kernel/softirq.c:644
common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:247
</IRQ>
<TASK>
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:636
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline]
RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:113
Code: 08 ed c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 65 48 8b 05 48 44 7c 75 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 78 ea b2 00 fb f4 <fa> c3 0f 1f 40 00 0f b6 47 08 3c 01 74 0b 3c 02 74 05 8b 7f 04 eb
RSP: 0018:ffffc90000187d58 EFLAGS: 00000246
RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8a875e35
RDX: 0000000000000001 RSI: ffff8881406f2800 RDI: ffff8881406f2864
RBP: ffff8881406f2864 R08: 0000000000000001 R09: ffffed1017326dbd
R10: ffff8880b9936deb R11: 0000000000000000 R12: ffff888145aa9000
R13: ffffffff8dd222e0 R14: 0000000000000001 R15: 0000000000000000
acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707
cpuidle_enter_state+0x83/0x500 drivers/cpuidle/cpuidle.c:267
cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388
cpuidle_idle_call kernel/sched/idle.c:215 [inline]
do_idle+0x314/0x3f0 kernel/sched/idle.c:312
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:410
start_secondary+0x20e/0x2a0 arch/x86/kernel/smpboot.c:336
secondary_startup_64_no_verify+0x166/0x16b
</TASK>
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 0 at lib/refcount.c:28 refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Modules linked in:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.7.0-rc4-next-20231205-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Code: ff 89 de e8 98 f4 22 fd 84 db 0f 85 66 ff ff ff e8 5b f9 22 fd c6 05 d1 8b be 0a 01 90 48 c7 c7 80 b6 2e 8b e8 47 e8 e8 fc 90 <0f> 0b 90 90 e9 43 ff ff ff e8 38 f9 22 fd 0f b6 1d ac 8b be 0a 31
RSP: 0018:ffffc900001f0aa0 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff814e05d9
RDX: ffff8880156b3b80 RSI: ffffffff814e05e6 RDI: 0000000000000001
RBP: ffff88803414001c R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff888017e9cdc0
R13: ffff888015abe800 R14: ffff888015abe85c R15: ffff8880b993c340
FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f34d02ffd04 CR3: 000000002fc42000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
__refcount_sub_and_test include/linux/refcount.h:283 [inline]
__refcount_dec_and_test include/linux/refcount.h:315 [inline]
refcount_dec_and_test include/linux/refcount.h:333 [inline]
stack_depot_put lib/stackdepot.c:627 [inline]
stack_depot_put+0xe4/0x110 lib/stackdepot.c:613
__kasan_record_aux_stack+0xb3/0xd0 mm/kasan/generic.c:515
insert_work+0x38/0x230 kernel/workqueue.c:1653
__queue_work+0x633/0x11d0 kernel/workqueue.c:1802
__queue_delayed_work+0x1bf/0x270 kernel/workqueue.c:1953
mod_delayed_work_on+0xcc/0x1a0 kernel/workqueue.c:2027
kblockd_mod_delayed_work_on+0x29/0x40 block/blk-core.c:1046
blk_kick_flush block/blk-flush.c:348 [inline]
blk_flush_complete_seq+0xa66/0x10c0 block/blk-flush.c:213
mq_flush_data_end_io+0x2e3/0x580 block/blk-flush.c:376
__blk_mq_end_request+0x248/0x4f0 block/blk-mq.c:1046
scsi_end_request+0x444/0x9a0 drivers/scsi/scsi_lib.c:572
scsi_io_completion+0x178/0x14c0 drivers/scsi/scsi_lib.c:975
scsi_complete+0x124/0x250 drivers/scsi/scsi_lib.c:1437
blk_complete_reqs+0xb2/0xf0 block/blk-mq.c:1131
__do_softirq+0x216/0x8d5 kernel/softirq.c:553
invoke_softirq kernel/softirq.c:427 [inline]
__irq_exit_rcu kernel/softirq.c:632 [inline]
irq_exit_rcu+0xb5/0x120 kernel/softirq.c:644
common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:247
</IRQ>
<TASK>
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:636
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline]
RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:113
Code: 08 ed c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 65 48 8b 05 48 44 7c 75 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 78 ea b2 00 fb f4 <fa> c3 0f 1f 40 00 0f b6 47 08 3c 01 74 0b 3c 02 74 05 8b 7f 04 eb
RSP: 0018:ffffc90000187d58 EFLAGS: 00000246
RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8a875e35
RDX: 0000000000000001 RSI: ffff8881406f2800 RDI: ffff8881406f2864
RBP: ffff8881406f2864 R08: 0000000000000001 R09: ffffed1017326dbd
R10: ffff8880b9936deb R11: 0000000000000000 R12: ffff888145aa9000
R13: ffffffff8dd222e0 R14: 0000000000000001 R15: 0000000000000000
acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707
cpuidle_enter_state+0x83/0x500 drivers/cpuidle/cpuidle.c:267
cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388
cpuidle_idle_call kernel/sched/idle.c:215 [inline]
do_idle+0x314/0x3f0 kernel/sched/idle.c:312
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:410
start_secondary+0x20e/0x2a0 arch/x86/kernel/smpboot.c:336
secondary_startup_64_no_verify+0x166/0x16b
</TASK>
----------------
Code disassembly (best guess):
0: 08 ed or %ch,%ch
2: c3 ret
3: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1)
a: 00 00 00 00
e: 66 90 xchg %ax,%ax
10: 65 48 8b 05 48 44 7c mov %gs:0x757c4448(%rip),%rax # 0x757c4460
17: 75
18: 48 8b 00 mov (%rax),%rax
1b: a8 08 test $0x8,%al
1d: 75 0c jne 0x2b
1f: 66 90 xchg %ax,%ax
21: 0f 00 2d 78 ea b2 00 verw 0xb2ea78(%rip) # 0xb2eaa0
28: fb sti
29: f4 hlt
* 2a: fa cli <-- trapping instruction
2b: c3 ret
2c: 0f 1f 40 00 nopl 0x0(%rax)
30: 0f b6 47 08 movzbl 0x8(%rdi),%eax
34: 3c 01 cmp $0x1,%al
36: 74 0b je 0x43
38: 3c 02 cmp $0x2,%al
3a: 74 05 je 0x41
3c: 8b 7f 04 mov 0x4(%rdi),%edi
3f: eb .byte 0xeb