Hello, We found the following issue using syzkaller on Linux v6.10. A possible deadlock issue was discovered in function `serial8250_console_write` when it attempted to acquire the lock `up->port->lock` ( executing `uart_port_lock_irqsave(port, &flags);` ) The full report including the Syzkaller reproducer: https://gist.github.com/TomAPU/5c1865d66f0183d1596d400df59c2919 The brief report is below: ------------[ cut here ]------------ ====================================================== WARNING: possible circular locking dependency detected 6.10.0 #13 Not tainted ------------------------------------------------------ swapper/0/0 is trying to acquire lock: ffffffff8db27200 (console_owner){..-.}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:334 [inline] ffffffff8db27200 (console_owner){..-.}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:232 [inline] ffffffff8db27200 (console_owner){..-.}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:286 [inline] ffffffff8db27200 (console_owner){..-.}-{0:0}, at: console_flush_all+0x14d/0xfb0 kernel/printk/printk.c:2971 but task is already holding lock: ffff888013098018 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x6d3/0xce0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&pool->lock){-.-.}-{2:2}: __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 __queue_work+0x6d3/0xce0 queue_work_on+0x18a/0x2d0 kernel/workqueue.c:2411 queue_work include/linux/workqueue.h:621 [inline] rpm_suspend+0x108a/0x1950 drivers/base/power/runtime.c:662 __pm_runtime_idle+0x12c/0x1a0 drivers/base/power/runtime.c:1104 pm_runtime_put include/linux/pm_runtime.h:448 [inline] __device_attach+0x3d4/0x500 drivers/base/dd.c:1046 bus_probe_device+0x1b1/0x290 drivers/base/bus.c:532 device_add+0x91d/0xd00 drivers/base/core.c:3679 serial_base_port_add+0x2ec/0x3c0 drivers/tty/serial/serial_base_bus.c:178 serial_core_port_device_add drivers/tty/serial/serial_core.c:3380 [inline] serial_core_register_port+0x386/0x21f0 drivers/tty/serial/serial_core.c:3421 serial8250_register_8250_port+0x142c/0x1c80 drivers/tty/serial/8250/8250_core.c:1135 serial_pnp_probe+0x4ed/0x9c0 drivers/tty/serial/8250/8250_pnp.c:490 pnp_device_probe+0x2b2/0x450 drivers/pnp/driver.c:111 call_driver_probe+0x9a/0x1b0 really_probe+0x274/0x8e0 drivers/base/dd.c:656 __driver_probe_device+0x199/0x380 drivers/base/dd.c:798 driver_probe_device+0x50/0x240 drivers/base/dd.c:828 __driver_attach+0x366/0x5a0 drivers/base/dd.c:1214 bus_for_each_dev+0x269/0x2e0 drivers/base/bus.c:368 bus_add_driver+0x369/0x680 drivers/base/bus.c:673 driver_register+0x236/0x310 drivers/base/driver.c:246 serial8250_init+0x96/0x170 drivers/tty/serial/8250/8250_core.c:1236 do_one_initcall+0xc4/0x310 init/main.c:1267 do_initcall_level+0x14e/0x270 init/main.c:1329 do_initcalls+0x3f/0x80 init/main.c:1345 kernel_init_freeable+0x42e/0x5c0 init/main.c:1578 kernel_init+0x19/0x2a0 init/main.c:1467 ret_from_fork+0x49/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244 -> #2 (&dev->power.lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 __pm_runtime_resume+0x10c/0x170 drivers/base/power/runtime.c:1171 pm_runtime_get include/linux/pm_runtime.h:396 [inline] __uart_start+0x17a/0x430 drivers/tty/serial/serial_core.c:148 uart_write+0x14c/0x370 drivers/tty/serial/serial_core.c:633 process_output_block drivers/tty/n_tty.c:574 [inline] n_tty_write+0xda5/0x12d0 drivers/tty/n_tty.c:2389 iterate_tty_write drivers/tty/tty_io.c:1021 [inline] file_tty_write+0x589/0xa00 drivers/tty/tty_io.c:1096 do_iter_readv_writev+0x4f6/0x730 vfs_writev+0x38c/0xc10 fs/read_write.c:971 do_writev+0x1ac/0x340 fs/read_write.c:1018 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x7e/0x150 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x67/0x6f -> #1 (&port_lock_key){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:618 [inline] serial8250_console_write+0x1a7/0x1750 drivers/tty/serial/8250/8250_port.c:3352 console_emit_next_record kernel/printk/printk.c:2913 [inline] console_flush_all+0x857/0xfb0 kernel/printk/printk.c:2979 console_unlock+0x136/0x4c0 kernel/printk/printk.c:3048 vprintk_emit+0x59d/0x760 kernel/printk/printk.c:2348 _printk+0xd1/0x120 kernel/printk/printk.c:2373 register_console+0x707/0xcb0 kernel/printk/printk.c:3581 univ8250_console_init+0x41/0x50 drivers/tty/serial/8250/8250_core.c:714 console_init+0x63/0xb0 kernel/printk/printk.c:3727 start_kernel+0x2df/0x500 init/main.c:1038 x86_64_start_reservations+0x26/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x5c/0x60 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 -> #0 (console_owner){..-.}-{0:0}: 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+0x37ac/0x8050 kernel/locking/lockdep.c:5137 lock_acquire+0x1a9/0x400 kernel/locking/lockdep.c:5754 console_lock_spinning_enable kernel/printk/printk.c:1873 [inline] console_emit_next_record kernel/printk/printk.c:2907 [inline] console_flush_all+0x800/0xfb0 kernel/printk/printk.c:2979 console_unlock+0x136/0x4c0 kernel/printk/printk.c:3048 vprintk_emit+0x59d/0x760 kernel/printk/printk.c:2348 _printk+0xd1/0x120 kernel/printk/printk.c:2373 __warn_printk+0x195/0x310 kernel/panic.c:737 debug_print_object lib/debugobjects.c:514 [inline] debug_object_activate+0x35a/0x4a0 lib/debugobjects.c:732 debug_work_activate kernel/workqueue.c:665 [inline] insert_work+0x36/0x320 kernel/workqueue.c:2205 __queue_work+0xb61/0xce0 kernel/workqueue.c:2360 queue_work_on+0x18a/0x2d0 kernel/workqueue.c:2411 __ieee80211_queue_skb_to_iface net/mac80211/rx.c:233 [inline] ieee80211_queue_skb_to_iface net/mac80211/rx.c:244 [inline] ieee80211_rx_h_mgmt+0x500/0x6f0 net/mac80211/rx.c:4047 ieee80211_rx_handlers+0x8109/0xb770 net/mac80211/rx.c:4205 ieee80211_invoke_rx_handlers net/mac80211/rx.c:4235 [inline] ieee80211_prepare_and_rx_handle+0x31ce/0x6270 net/mac80211/rx.c:5083 __ieee80211_rx_handle_packet net/mac80211/rx.c:5324 [inline] ieee80211_rx_list+0x2ba2/0x35f0 net/mac80211/rx.c:5459 ieee80211_rx_napi+0x186/0x3b0 net/mac80211/rx.c:5482 ieee80211_rx include/net/mac80211.h:5093 [inline] ieee80211_handle_queued_frames+0xff/0x190 net/mac80211/main.c:438 tasklet_action_common+0x3e8/0x5f0 kernel/softirq.c:785 handle_softirqs+0x272/0x750 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf0/0x1b0 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:702 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] default_idle+0xb/0x10 arch/x86/kernel/process.c:742 default_idle_call+0x6e/0xa0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x22b/0x5c0 kernel/sched/idle.c:332 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:430 rest_init+0x2db/0x300 init/main.c:747 start_kernel+0x486/0x500 init/main.c:1103 x86_64_start_reservations+0x26/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x5c/0x60 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 other info that might help us debug this: Chain exists of: console_owner --> &dev->power.lock --> &pool->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pool->lock); lock(&dev->power.lock); lock(&pool->lock); lock(console_owner); *** DEADLOCK *** 6 locks held by swapper/0/0: #0: ffffffff8db32fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8db32fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8db32fe0 (rcu_read_lock){....}-{1:2}, at: ieee80211_rx_napi+0xd2/0x3b0 net/mac80211/rx.c:5481 #1: ffff88803bad96d0 (&local->rx_path_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff88803bad96d0 (&local->rx_path_lock){+.-.}-{2:2}, at: ieee80211_rx_handlers+0xf7/0xb770 net/mac80211/rx.c:4171 #2: ffffffff8db32fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #2: ffffffff8db32fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #2: ffffffff8db32fe0 (rcu_read_lock){....}-{1:2}, at: __queue_work+0x196/0xce0 kernel/workqueue.c:2284 #3: ffff888013098018 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x6d3/0xce0 #4: ffffffff8da0eb20 (console_lock){+.+.}-{0:0}, at: _printk+0xd1/0x120 kernel/printk/printk.c:2373 #5: ffffffff8da0e750 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:334 [inline] #5: ffffffff8da0e750 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:232 [inline] #5: ffffffff8da0e750 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:286 [inline] #5: ffffffff8da0e750 (console_srcu){....}-{0:0}, at: console_flush_all+0x14d/0xfb0 kernel/printk/printk.c:2971 stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.10.0 #13 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x23d/0x360 lib/dump_stack.c:114 check_noncircular+0x36c/0x4a0 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+0x37ac/0x8050 kernel/locking/lockdep.c:5137 lock_acquire+0x1a9/0x400 kernel/locking/lockdep.c:5754 console_lock_spinning_enable kernel/printk/printk.c:1873 [inline] console_emit_next_record kernel/printk/printk.c:2907 [inline] console_flush_all+0x800/0xfb0 kernel/printk/printk.c:2979 console_unlock+0x136/0x4c0 kernel/printk/printk.c:3048 vprintk_emit+0x59d/0x760 kernel/printk/printk.c:2348 _printk+0xd1/0x120 kernel/printk/printk.c:2373 __warn_printk+0x195/0x310 kernel/panic.c:737 debug_print_object lib/debugobjects.c:514 [inline] debug_object_activate+0x35a/0x4a0 lib/debugobjects.c:732 debug_work_activate kernel/workqueue.c:665 [inline] insert_work+0x36/0x320 kernel/workqueue.c:2205 __queue_work+0xb61/0xce0 kernel/workqueue.c:2360 queue_work_on+0x18a/0x2d0 kernel/workqueue.c:2411 __ieee80211_queue_skb_to_iface net/mac80211/rx.c:233 [inline] ieee80211_queue_skb_to_iface net/mac80211/rx.c:244 [inline] ieee80211_rx_h_mgmt+0x500/0x6f0 net/mac80211/rx.c:4047 ieee80211_rx_handlers+0x8109/0xb770 net/mac80211/rx.c:4205 ieee80211_invoke_rx_handlers net/mac80211/rx.c:4235 [inline] ieee80211_prepare_and_rx_handle+0x31ce/0x6270 net/mac80211/rx.c:5083 __ieee80211_rx_handle_packet net/mac80211/rx.c:5324 [inline] ieee80211_rx_list+0x2ba2/0x35f0 net/mac80211/rx.c:5459 ieee80211_rx_napi+0x186/0x3b0 net/mac80211/rx.c:5482 ieee80211_rx include/net/mac80211.h:5093 [inline] ieee80211_handle_queued_frames+0xff/0x190 net/mac80211/main.c:438 tasklet_action_common+0x3e8/0x5f0 kernel/softirq.c:785 handle_softirqs+0x272/0x750 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf0/0x1b0 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1043 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:702 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:default_idle+0xb/0x10 arch/x86/kernel/process.c:743 Code: 07 76 e7 48 89 07 49 c7 c0 08 00 00 00 4d 29 c8 4c 01 c7 4c 29 c2 e9 72 ff ff ff cc cc cc cc 66 90 0f 00 2d c7 a4 4e 00 fb f4 <fa> c3 0f 1f 00 e9 eb ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 65 RSP: 0018:ffffffff8d807d68 EFLAGS: 000002c2 RAX: ddff7d1dfa769700 RBX: ffffffff816928eb RCX: 0000000000014109 RDX: 0000000000000001 RSI: ffffffff8b4c89c0 RDI: ffffffff8ba956e0 RBP: ffffffff8d807eb8 R08: ffff888063a37d0b R09: 1ffff1100c746fa1 R10: dffffc0000000000 R11: ffffed100c746fa2 R12: 1ffffffff1b00fc6 R13: 1ffffffff1b12778 R14: 0000000000000000 R15: dffffc0000000000 default_idle_call+0x6e/0xa0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x22b/0x5c0 kernel/sched/idle.c:332 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:430 rest_init+0x2db/0x300 init/main.c:747 start_kernel+0x486/0x500 init/main.c:1103 x86_64_start_reservations+0x26/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x5c/0x60 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 </TASK> ODEBUG: activate not available (active state 0) object: ffff88803bad8660 object type: work_struct hint: cfg80211_wiphy_work+0x0/0x260 WARNING: CPU: 0 PID: 0 at lib/debugobjects.c:517 debug_print_object lib/debugobjects.c:514 [inline] WARNING: CPU: 0 PID: 0 at lib/debugobjects.c:517 debug_object_activate+0x35e/0x4a0 lib/debugobjects.c:732 Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.10.0 #13 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:debug_print_object lib/debugobjects.c:514 [inline] RIP: 0010:debug_object_activate+0x35e/0x4a0 lib/debugobjects.c:732 Code: 8b 4d 00 48 c7 c7 a0 61 a9 8b 48 c7 c6 c0 5d a9 8b 4c 89 e2 8b 4c 24 0c 4c 8b 44 24 18 ff 74 24 10 e8 a6 3c f7 fc 48 83 c4 08 <0f> 0b 48 8b 1c 24 ff 05 06 2e c6 0a bd ea ff ff ff 83 fb 05 74 05 RSP: 0018:ffffc90000007190 EFLAGS: 00010096 RAX: ddff7d1dfa769700 RBX: ffffffff8ba96248 RCX: ffffffff8d893bc0 RDX: 0000000000000303 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff8b4b7d20 R08: ffffffff8155a25a R09: 1ffff1100c74519a R10: dffffc0000000000 R11: ffffed100c74519b R12: ffffffff8ba96360 R13: ffffffff8b4b7d20 R14: dffffc0000000000 R15: ffff88803bad8660 FS: 0000000000000000(0000) GS:ffff888063a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000558a63a431d0 CR3: 000000000d932000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> debug_work_activate kernel/workqueue.c:665 [inline] insert_work+0x36/0x320 kernel/workqueue.c:2205 __queue_work+0xb61/0xce0 kernel/workqueue.c:2360 queue_work_on+0x18a/0x2d0 kernel/workqueue.c:2411 __ieee80211_queue_skb_to_iface net/mac80211/rx.c:233 [inline] ieee80211_queue_skb_to_iface net/mac80211/rx.c:244 [inline] ieee80211_rx_h_mgmt+0x500/0x6f0 net/mac80211/rx.c:4047 ieee80211_rx_handlers+0x8109/0xb770 net/mac80211/rx.c:4205 ieee80211_invoke_rx_handlers net/mac80211/rx.c:4235 [inline] ieee80211_prepare_and_rx_handle+0x31ce/0x6270 net/mac80211/rx.c:5083 __ieee80211_rx_handle_packet net/mac80211/rx.c:5324 [inline] ieee80211_rx_list+0x2ba2/0x35f0 net/mac80211/rx.c:5459 ieee80211_rx_napi+0x186/0x3b0 net/mac80211/rx.c:5482 ieee80211_rx include/net/mac80211.h:5093 [inline] ieee80211_handle_queued_frames+0xff/0x190 net/mac80211/main.c:438 tasklet_action_common+0x3e8/0x5f0 kernel/softirq.c:785 handle_softirqs+0x272/0x750 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf0/0x1b0 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1043 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:702 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:default_idle+0xb/0x10 arch/x86/kernel/process.c:743 Code: 07 76 e7 48 89 07 49 c7 c0 08 00 00 00 4d 29 c8 4c 01 c7 4c 29 c2 e9 72 ff ff ff cc cc cc cc 66 90 0f 00 2d c7 a4 4e 00 fb f4 <fa> c3 0f 1f 00 e9 eb ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 65 RSP: 0018:ffffffff8d807d68 EFLAGS: 000002c2 RAX: ddff7d1dfa769700 RBX: ffffffff816928eb RCX: 0000000000014109 RDX: 0000000000000001 RSI: ffffffff8b4c89c0 RDI: ffffffff8ba956e0 RBP: ffffffff8d807eb8 R08: ffff888063a37d0b R09: 1ffff1100c746fa1 R10: dffffc0000000000 R11: ffffed100c746fa2 R12: 1ffffffff1b00fc6 R13: 1ffffffff1b12778 R14: 0000000000000000 R15: dffffc0000000000 default_idle_call+0x6e/0xa0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x22b/0x5c0 kernel/sched/idle.c:332 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:430 rest_init+0x2db/0x300 init/main.c:747 start_kernel+0x486/0x500 init/main.c:1103 x86_64_start_reservations+0x26/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x5c/0x60 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 </TASK> ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 76 e7 jbe 0xffffffe9 2: 48 89 07 mov %rax,(%rdi) 5: 49 c7 c0 08 00 00 00 mov $0x8,%r8 c: 4d 29 c8 sub %r9,%r8 f: 4c 01 c7 add %r8,%rdi 12: 4c 29 c2 sub %r8,%rdx 15: e9 72 ff ff ff jmp 0xffffff8c 1a: cc int3 1b: cc int3 1c: cc int3 1d: cc int3 1e: 66 90 xchg %ax,%ax 20: 0f 00 2d c7 a4 4e 00 verw 0x4ea4c7(%rip) # 0x4ea4ee 27: fb sti 28: f4 hlt * 29: fa cli <-- trapping instruction 2a: c3 ret 2b: 0f 1f 00 nopl (%rax) 2e: e9 eb ff ff ff jmp 0x1e 33: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 3a: 00 00 00 3d: 90 nop 3e: 65 gs
