======================================================== WARNING: possible irq lock inversion dependency detected 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted -------------------------------------------------------- syz-executor.4/5315 just changed the state of lock: ffff888029d06910 (&group->lock#2){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 but this lock took another, SOFTIRQ-unsafe lock in the past: (&timer->lock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&timer->lock); local_irq_disable(); lock(&group->lock#2); lock(&timer->lock); lock(&group->lock#2); *** DEADLOCK *** 2 locks held by syz-executor.4/5315: #0: ffffffff8d79e2e0 (console_lock){+.+.}-{0:0}, at: vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45 #1: ffffffff8d79e350 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:303 [inline] #1: ffffffff8d79e350 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:232 [inline] #1: ffffffff8d79e350 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:286 [inline] #1: ffffffff8d79e350 (console_srcu){....}-{0:0}, at: console_flush_all+0x12d/0xd70 kernel/printk/printk.c:2965 the shortest dependencies between 2nd lock and 1st lock: -> (&timer->lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x65/0xbd0 sound/core/timer.c:412 snd_timer_close+0x8b/0xf0 sound/core/timer.c:464 snd_seq_timer_close+0xa4/0x100 sound/core/seq/seq_timer.c:302 queue_delete+0x49/0xa0 sound/core/seq/seq_queue.c:126 snd_seq_queue_delete+0x45/0x60 sound/core/seq/seq_queue.c:188 snd_seq_kernel_client_ctl+0x107/0x1c0 sound/core/seq/seq_clientmgr.c:2526 delete_seq_queue.isra.0+0xc8/0x150 sound/core/seq/oss/seq_oss_init.c:371 odev_release+0x52/0x80 sound/core/seq/oss/seq_oss.c:144 __fput+0x270/0xb80 fs/file_table.c:422 __fput_sync+0x47/0x50 fs/file_table.c:507 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x86/0x100 fs/open.c:1541 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 SOFTIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x65/0xbd0 sound/core/timer.c:412 snd_timer_close+0x8b/0xf0 sound/core/timer.c:464 snd_seq_timer_close+0xa4/0x100 sound/core/seq/seq_timer.c:302 queue_delete+0x49/0xa0 sound/core/seq/seq_queue.c:126 snd_seq_queue_delete+0x45/0x60 sound/core/seq/seq_queue.c:188 snd_seq_kernel_client_ctl+0x107/0x1c0 sound/core/seq/seq_clientmgr.c:2526 delete_seq_queue.isra.0+0xc8/0x150 sound/core/seq/oss/seq_oss_init.c:371 odev_release+0x52/0x80 sound/core/seq/oss/seq_oss.c:144 __fput+0x270/0xb80 fs/file_table.c:422 __fput_sync+0x47/0x50 fs/file_table.c:507 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x86/0x100 fs/open.c:1541 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x65/0xbd0 sound/core/timer.c:412 snd_timer_close+0x8b/0xf0 sound/core/timer.c:464 snd_seq_timer_close+0xa4/0x100 sound/core/seq/seq_timer.c:302 queue_delete+0x49/0xa0 sound/core/seq/seq_queue.c:126 snd_seq_queue_delete+0x45/0x60 sound/core/seq/seq_queue.c:188 snd_seq_kernel_client_ctl+0x107/0x1c0 sound/core/seq/seq_clientmgr.c:2526 delete_seq_queue.isra.0+0xc8/0x150 sound/core/seq/oss/seq_oss_init.c:371 odev_release+0x52/0x80 sound/core/seq/oss/seq_oss.c:144 __fput+0x270/0xb80 fs/file_table.c:422 __fput_sync+0x47/0x50 fs/file_table.c:507 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x86/0x100 fs/open.c:1541 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 } ... key at: [] __key.6+0x0/0x40 ... acquired at: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x111/0x3e0 sound/core/timer.c:1040 snd_pcm_timer_notify sound/core/pcm_native.c:622 [inline] snd_pcm_post_start+0x272/0x350 sound/core/pcm_native.c:1459 snd_pcm_action_single+0x10a/0x150 sound/core/pcm_native.c:1289 snd_pcm_action+0x70/0x90 sound/core/pcm_native.c:1370 __snd_pcm_lib_xfer+0x13f5/0x1ea0 sound/core/pcm_lib.c:2371 snd_pcm_oss_write3+0xd5/0x1e0 sound/core/oss/pcm_oss.c:1242 io_playback_transfer+0x273/0x300 sound/core/oss/io.c:47 snd_pcm_plug_write_transfer+0x2cd/0x410 sound/core/oss/pcm_plugin.c:630 snd_pcm_oss_write2+0x24f/0x3f0 sound/core/oss/pcm_oss.c:1374 snd_pcm_oss_sync1+0x1bf/0x510 sound/core/oss/pcm_oss.c:1616 snd_pcm_oss_sync+0x617/0x7f0 sound/core/oss/pcm_oss.c:1692 snd_pcm_oss_ioctl+0x1150/0x37a0 sound/core/oss/pcm_oss.c:2619 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl fs/ioctl.c:890 [inline] __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:890 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 -> (&group->lock#2){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x20/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x9d/0x1c0 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x20c/0xc20 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1773 __do_softirq+0x218/0x8de kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 console_flush_all+0xa19/0xd70 kernel/printk/printk.c:2979 console_unlock+0xae/0x290 kernel/printk/printk.c:3042 vprintk_emit kernel/printk/printk.c:2342 [inline] vprintk_emit+0x11a/0x5a0 kernel/printk/printk.c:2297 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2367 tcpmss_tg4_check+0x2a3/0x360 net/netfilter/xt_TCPMSS.c:273 xt_check_target+0x272/0xa30 net/netfilter/x_tables.c:1038 check_target net/ipv4/netfilter/ip_tables.c:510 [inline] find_check_entry.constprop.0+0x7d6/0x9d0 net/ipv4/netfilter/ip_tables.c:552 translate_table+0xc93/0x1710 net/ipv4/netfilter/ip_tables.c:716 do_replace net/ipv4/netfilter/ip_tables.c:1133 [inline] do_ipt_set_ctl+0x5a8/0xbe0 net/ipv4/netfilter/ip_tables.c:1627 nf_setsockopt+0x8a/0xf0 net/netfilter/nf_sockopt.c:101 ip_setsockopt+0xcb/0xf0 net/ipv4/ip_sockglue.c:1424 udp_setsockopt+0x7d/0xd0 net/ipv4/udp.c:2783 do_sock_setsockopt+0x222/0x480 net/socket.c:2311 __sys_setsockopt+0x1a4/0x270 net/socket.c:2334 __do_sys_setsockopt net/socket.c:2343 [inline] __se_sys_setsockopt net/socket.c:2340 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2340 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] snd_pcm_group_lock_irq sound/core/pcm_native.c:97 [inline] snd_pcm_stream_lock_irq sound/core/pcm_native.c:136 [inline] class_pcm_stream_lock_irq_constructor include/sound/pcm.h:666 [inline] snd_pcm_hw_params+0x151/0x1a30 sound/core/pcm_native.c:740 snd_pcm_kernel_ioctl+0x147/0x2d0 sound/core/pcm_native.c:3434 snd_pcm_oss_change_params_locked+0x146c/0x3aa0 sound/core/oss/pcm_oss.c:965 snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1105 [inline] snd_pcm_oss_get_active_substream+0x168/0x1d0 sound/core/oss/pcm_oss.c:1122 snd_pcm_oss_get_formats+0x7e/0x330 sound/core/oss/pcm_oss.c:1843 snd_pcm_oss_set_format sound/core/oss/pcm_oss.c:1883 [inline] snd_pcm_oss_ioctl+0x2ef7/0x37a0 sound/core/oss/pcm_oss.c:2648 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl fs/ioctl.c:890 [inline] __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:890 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 } ... key at: [] __key.5+0x0/0x40 ... acquired at: mark_usage kernel/locking/lockdep.c:4567 [inline] __lock_acquire+0x13d4/0x3b30 kernel/locking/lockdep.c:5091 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x20/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x9d/0x1c0 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x20c/0xc20 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1773 __do_softirq+0x218/0x8de kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 console_flush_all+0xa19/0xd70 kernel/printk/printk.c:2979 console_unlock+0xae/0x290 kernel/printk/printk.c:3042 vprintk_emit kernel/printk/printk.c:2342 [inline] vprintk_emit+0x11a/0x5a0 kernel/printk/printk.c:2297 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2367 tcpmss_tg4_check+0x2a3/0x360 net/netfilter/xt_TCPMSS.c:273 xt_check_target+0x272/0xa30 net/netfilter/x_tables.c:1038 check_target net/ipv4/netfilter/ip_tables.c:510 [inline] find_check_entry.constprop.0+0x7d6/0x9d0 net/ipv4/netfilter/ip_tables.c:552 translate_table+0xc93/0x1710 net/ipv4/netfilter/ip_tables.c:716 do_replace net/ipv4/netfilter/ip_tables.c:1133 [inline] do_ipt_set_ctl+0x5a8/0xbe0 net/ipv4/netfilter/ip_tables.c:1627 nf_setsockopt+0x8a/0xf0 net/netfilter/nf_sockopt.c:101 ip_setsockopt+0xcb/0xf0 net/ipv4/ip_sockglue.c:1424 udp_setsockopt+0x7d/0xd0 net/ipv4/udp.c:2783 do_sock_setsockopt+0x222/0x480 net/socket.c:2311 __sys_setsockopt+0x1a4/0x270 net/socket.c:2334 __do_sys_setsockopt net/socket.c:2343 [inline] __se_sys_setsockopt net/socket.c:2340 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2340 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 stack backtrace: CPU: 1 PID: 5315 Comm: syz-executor.4 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 print_irq_inversion_bug.part.0+0x3e9/0x5a0 kernel/locking/lockdep.c:4080 print_irq_inversion_bug kernel/locking/lockdep.c:4033 [inline] check_usage_forwards kernel/locking/lockdep.c:4111 [inline] mark_lock_irq kernel/locking/lockdep.c:4243 [inline] mark_lock+0x574/0xc60 kernel/locking/lockdep.c:4678 mark_usage kernel/locking/lockdep.c:4567 [inline] __lock_acquire+0x13d4/0x3b30 kernel/locking/lockdep.c:5091 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 _snd_pcm_stream_lock_irqsave+0xa0/0xd0 sound/core/pcm_native.c:170 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x20/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x9d/0x1c0 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x20c/0xc20 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1773 __do_softirq+0x218/0x8de kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_flush_all+0xa19/0xd70 kernel/printk/printk.c:2979 Code: e8 9c dd 25 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 0a c9 1e 00 48 85 db 0f 85 8b 01 00 00 e8 ec cd 1e 00 fb 48 8b 04 24 <4c> 89 fa 83 e2 07 0f b6 00 38 d0 7f 08 84 c0 0f 85 a9 02 00 00 41 RSP: 0018:ffffc90002daf358 EFLAGS: 00000283 RAX: fffff520005b5e92 RBX: 0000000000000000 RCX: ffffc9000a24b000 RDX: 0000000000040000 RSI: ffffffff816e2ac4 RDI: 0000000000000007 RBP: dffffc0000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000003 R12: 0000000000000200 R13: ffffffff8e3995f8 R14: ffffffff8e3995a0 R15: ffffc90002daf490 console_unlock+0xae/0x290 kernel/printk/printk.c:3042 vprintk_emit kernel/printk/printk.c:2342 [inline] vprintk_emit+0x11a/0x5a0 kernel/printk/printk.c:2297 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2367 tcpmss_tg4_check+0x2a3/0x360 net/netfilter/xt_TCPMSS.c:273 xt_check_target+0x272/0xa30 net/netfilter/x_tables.c:1038 check_target net/ipv4/netfilter/ip_tables.c:510 [inline] find_check_entry.constprop.0+0x7d6/0x9d0 net/ipv4/netfilter/ip_tables.c:552 translate_table+0xc93/0x1710 net/ipv4/netfilter/ip_tables.c:716 do_replace net/ipv4/netfilter/ip_tables.c:1133 [inline] do_ipt_set_ctl+0x5a8/0xbe0 net/ipv4/netfilter/ip_tables.c:1627 nf_setsockopt+0x8a/0xf0 net/netfilter/nf_sockopt.c:101 ip_setsockopt+0xcb/0xf0 net/ipv4/ip_sockglue.c:1424 udp_setsockopt+0x7d/0xd0 net/ipv4/udp.c:2783 do_sock_setsockopt+0x222/0x480 net/socket.c:2311 __sys_setsockopt+0x1a4/0x270 net/socket.c:2334 __do_sys_setsockopt net/socket.c:2343 [inline] __se_sys_setsockopt net/socket.c:2340 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2340 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f5ffd87de69 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5ffe5110c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f5ffd9abf80 RCX: 00007f5ffd87de69 RDX: 0000000000000040 RSI: 0004000000000000 RDI: 0000000000000008 RBP: 00007f5ffd8ca47a R08: 0000000000000260 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f5ffd9abf80 R15: 00007fff8bc96388 ---------------- Code disassembly (best guess): 0: e8 9c dd 25 00 call 0x25dda1 5: 9c pushf 6: 5b pop %rbx 7: 81 e3 00 02 00 00 and $0x200,%ebx d: 31 ff xor %edi,%edi f: 48 89 de mov %rbx,%rsi 12: e8 0a c9 1e 00 call 0x1ec921 17: 48 85 db test %rbx,%rbx 1a: 0f 85 8b 01 00 00 jne 0x1ab 20: e8 ec cd 1e 00 call 0x1ece11 25: fb sti 26: 48 8b 04 24 mov (%rsp),%rax * 2a: 4c 89 fa mov %r15,%rdx <-- trapping instruction 2d: 83 e2 07 and $0x7,%edx 30: 0f b6 00 movzbl (%rax),%eax 33: 38 d0 cmp %dl,%al 35: 7f 08 jg 0x3f 37: 84 c0 test %al,%al 39: 0f 85 a9 02 00 00 jne 0x2e8 3f: 41 rex.B