================================ WARNING: inconsistent lock state 5.16.0-rc4-next-20211210-syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz-executor.4/7416 [HC0[0]:SC1[7]:HE1:SE0] takes: ffffffff8bca9b40 (fs_reclaim){+.?.}-{0:0}, at: might_alloc include/linux/sched/mm.h:253 [inline] ffffffff8bca9b40 (fs_reclaim){+.?.}-{0:0}, at: slab_pre_alloc_hook mm/slab.h:739 [inline] ffffffff8bca9b40 (fs_reclaim){+.?.}-{0:0}, at: slab_alloc_node mm/slub.c:3145 [inline] ffffffff8bca9b40 (fs_reclaim){+.?.}-{0:0}, at: slab_alloc mm/slub.c:3239 [inline] ffffffff8bca9b40 (fs_reclaim){+.?.}-{0:0}, at: kmem_cache_alloc_trace+0x3b/0x2c0 mm/slub.c:3256 {SOFTIRQ-ON-W} state was registered at: lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __fs_reclaim_acquire mm/page_alloc.c:4550 [inline] fs_reclaim_acquire+0x115/0x160 mm/page_alloc.c:4564 might_alloc include/linux/sched/mm.h:253 [inline] slab_pre_alloc_hook mm/slab.h:739 [inline] slab_alloc_node mm/slub.c:3145 [inline] slab_alloc mm/slub.c:3239 [inline] kmem_cache_alloc_trace+0x3b/0x2c0 mm/slub.c:3256 kmalloc include/linux/slab.h:581 [inline] kzalloc include/linux/slab.h:715 [inline] alloc_workqueue_attrs+0x38/0x80 kernel/workqueue.c:3405 wq_numa_init kernel/workqueue.c:5972 [inline] workqueue_init+0x12f/0x9e3 kernel/workqueue.c:6099 kernel_init_freeable+0x3fb/0x73a init/main.c:1602 kernel_init+0x1a/0x1d0 init/main.c:1507 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 irq event stamp: 8140 hardirqs last enabled at (8140): [] asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 hardirqs last disabled at (8139): [] sysvec_apic_timer_interrupt+0xb/0xc0 arch/x86/kernel/apic/apic.c:1097 softirqs last enabled at (7024): [] spin_unlock_bh include/linux/spinlock.h:399 [inline] softirqs last enabled at (7024): [] tipc_conn_kref_release+0x28e/0x380 net/tipc/topsrv.c:141 softirqs last disabled at (7097): [] invoke_softirq kernel/softirq.c:432 [inline] softirqs last disabled at (7097): [] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(fs_reclaim); lock(fs_reclaim); *** DEADLOCK *** 10 locks held by syz-executor.4/7416: #0: ffff888073a56210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:777 [inline] #0: ffff888073a56210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:648 #1: ffff88804140c4b0 (sk_lock-AF_TIPC){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1675 [inline] #1: ffff88804140c4b0 (sk_lock-AF_TIPC){+.+.}-{0:0}, at: tipc_release+0xc2/0x1a80 net/tipc/socket.c:638 #2: ffffc90000dc0d70 ((&ndev->rs_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:35 [inline] #2: ffffc90000dc0d70 ((&ndev->rs_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 kernel/time/timer.c:1411 #3: ffffffff8bb818a0 (rcu_read_lock){....}-{1:2}, at: ip6_nd_hdr net/ipv6/ndisc.c:466 [inline] #3: ffffffff8bb818a0 (rcu_read_lock){....}-{1:2}, at: ndisc_send_skb+0x84b/0x17f0 net/ipv6/ndisc.c:502 #4: ffffffff8bb81840 (rcu_read_lock_bh){....}-{1:2}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:95 [inline] #4: ffffffff8bb81840 (rcu_read_lock_bh){....}-{1:2}, at: ip6_finish_output2+0x2ad/0x14f0 net/ipv6/ip6_output.c:112 #5: ffffffff8bb81840 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1e3/0x3640 net/core/dev.c:4036 #6: ffffffff8bb818a0 (rcu_read_lock){....}-{1:2}, at: geneve_xmit+0xde/0x3530 drivers/net/geneve.c:1068 #7: ffffffff8bb818a0 (rcu_read_lock){....}-{1:2}, at: ip6_route_output_flags+0x0/0x320 net/ipv6/route.c:778 #8: ffffffff8bb818a0 (rcu_read_lock){....}-{1:2}, at: ip6_pol_route+0x156/0x11e0 net/ipv6/route.c:2217 #9: ffffffff8bb81840 (rcu_read_lock_bh){....}-{1:2}, at: rt6_probe net/ipv6/route.c:632 [inline] #9: ffffffff8bb81840 (rcu_read_lock_bh){....}-{1:2}, at: find_match.part.0+0x35a/0xd00 net/ipv6/route.c:752 stack backtrace: CPU: 1 PID: 7416 Comm: syz-executor.4 Not tainted 5.16.0-rc4-next-20211210-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_usage_bug kernel/locking/lockdep.c:203 [inline] valid_state kernel/locking/lockdep.c:3945 [inline] mark_lock_irq kernel/locking/lockdep.c:4148 [inline] mark_lock.cold+0x61/0x8e kernel/locking/lockdep.c:4605 mark_usage kernel/locking/lockdep.c:4500 [inline] __lock_acquire+0x11d5/0x54a0 kernel/locking/lockdep.c:4981 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __fs_reclaim_acquire mm/page_alloc.c:4550 [inline] fs_reclaim_acquire+0x115/0x160 mm/page_alloc.c:4564 might_alloc include/linux/sched/mm.h:253 [inline] slab_pre_alloc_hook mm/slab.h:739 [inline] slab_alloc_node mm/slub.c:3145 [inline] slab_alloc mm/slub.c:3239 [inline] kmem_cache_alloc_trace+0x3b/0x2c0 mm/slub.c:3256 kmalloc include/linux/slab.h:581 [inline] kzalloc include/linux/slab.h:715 [inline] ref_tracker_alloc+0xe1/0x430 lib/ref_tracker.c:74 netdev_tracker_alloc include/linux/netdevice.h:3860 [inline] dev_hold_track include/linux/netdevice.h:3877 [inline] rt6_probe net/ipv6/route.c:661 [inline] find_match.part.0+0xac9/0xd00 net/ipv6/route.c:752 find_match net/ipv6/route.c:825 [inline] __find_rr_leaf+0x17f/0xd20 net/ipv6/route.c:826 find_rr_leaf net/ipv6/route.c:847 [inline] rt6_select net/ipv6/route.c:891 [inline] fib6_table_lookup+0x649/0xa20 net/ipv6/route.c:2185 ip6_pol_route+0x1c5/0x11e0 net/ipv6/route.c:2221 pol_lookup_func include/net/ip6_fib.h:580 [inline] fib6_rule_lookup+0x52a/0x6f0 net/ipv6/fib6_rules.c:120 ip6_route_output_flags_noref+0x2e2/0x380 net/ipv6/route.c:2629 ip6_route_output_flags+0x72/0x320 net/ipv6/route.c:2642 ip6_route_output include/net/ip6_route.h:98 [inline] ip6_dst_lookup_tail+0x5ab/0x1620 net/ipv6/ip6_output.c:1070 ip6_dst_lookup_flow+0x8c/0x1d0 net/ipv6/ip6_output.c:1200 geneve_get_v6_dst+0x46f/0x9a0 drivers/net/geneve.c:858 geneve6_xmit_skb drivers/net/geneve.c:991 [inline] geneve_xmit+0x520/0x3530 drivers/net/geneve.c:1074 __netdev_start_xmit include/linux/netdevice.h:4685 [inline] netdev_start_xmit include/linux/netdevice.h:4699 [inline] xmit_one net/core/dev.c:3473 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3489 __dev_queue_xmit+0x2983/0x3640 net/core/dev.c:4112 neigh_resolve_output net/core/neighbour.c:1522 [inline] neigh_resolve_output+0x50e/0x820 net/core/neighbour.c:1502 neigh_output include/net/neighbour.h:541 [inline] ip6_finish_output2+0x56e/0x14f0 net/ipv6/ip6_output.c:126 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline] __ip6_finish_output+0x61e/0xe80 net/ipv6/ip6_output.c:170 ip6_finish_output+0x32/0x200 net/ipv6/ip6_output.c:201 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:224 dst_output include/net/dst.h:451 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ndisc_send_skb+0xa99/0x17f0 net/ipv6/ndisc.c:508 ndisc_send_rs+0x12e/0x6f0 net/ipv6/ndisc.c:702 addrconf_rs_timer+0x3f2/0x820 net/ipv6/addrconf.c:3898 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:unwind_next_frame+0xdeb/0x1ce0 arch/x86/kernel/unwind_orc.c:593 Code: 85 75 0d 00 00 83 e1 07 38 c8 0f 9e c2 84 c0 0f 95 c0 84 c2 0f 85 60 0d 00 00 41 0f b6 40 04 c0 e8 04 3c 01 0f 84 98 05 00 00 <3c> 04 74 21 84 c0 0f 84 b6 00 00 00 80 3d 86 bf 49 0c 00 0f b6 f0 RSP: 0018:ffffc9000291f6b0 EFLAGS: 00000297 RAX: 0000000000000000 RBX: 1ffff92000523ede RCX: 0000000000000001 RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffc9000291f7e0 RBP: 0000000000000001 R08: ffffffff8e199f54 R09: 0000000000000001 R10: fffff52000523efc R11: 000000000008808a R12: ffffc9000291fae8 R13: ffffc9000291f7bd R14: ffffc9000291f788 R15: ffffffff8e199f58 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:236 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3510 [inline] kfree+0xd0/0x4b0 mm/slub.c:4561 tipc_group_delete+0x2ff/0x450 net/tipc/group.c:229 tipc_sk_leave net/tipc/socket.c:3115 [inline] tipc_release+0x1f4/0x1a80 net/tipc/socket.c:643 __sock_release+0xcd/0x280 net/socket.c:649 sock_close+0x18/0x20 net/socket.c:1314 __fput+0x286/0x9f0 fs/file_table.c:311 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f0de6db6e99 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0de572c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000124 RAX: 0000000000000003 RBX: 00007f0de6ec9f60 RCX: 00007f0de6db6e99 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000004 RBP: 00007f0de6e10ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff3968b39f R14: 00007f0de572c300 R15: 0000000000022000 BUG: sleeping function called from invalid context at include/linux/sched/mm.h:256 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 7416, name: syz-executor.4 preempt_count: 701, expected: 0 RCU nest depth: 4, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [] unwind_next_frame+0x120/0x1ce0 arch/x86/kernel/unwind_orc.c:428 CPU: 1 PID: 7416 Comm: syz-executor.4 Not tainted 5.16.0-rc4-next-20211210-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 __might_resched.cold+0x222/0x26b kernel/sched/core.c:9583 might_alloc include/linux/sched/mm.h:256 [inline] slab_pre_alloc_hook mm/slab.h:739 [inline] slab_alloc_node mm/slub.c:3145 [inline] slab_alloc mm/slub.c:3239 [inline] kmem_cache_alloc_trace+0x25d/0x2c0 mm/slub.c:3256 kmalloc include/linux/slab.h:581 [inline] kzalloc include/linux/slab.h:715 [inline] ref_tracker_alloc+0xe1/0x430 lib/ref_tracker.c:74 netdev_tracker_alloc include/linux/netdevice.h:3860 [inline] dev_hold_track include/linux/netdevice.h:3877 [inline] rt6_probe net/ipv6/route.c:661 [inline] find_match.part.0+0xac9/0xd00 net/ipv6/route.c:752 find_match net/ipv6/route.c:825 [inline] __find_rr_leaf+0x17f/0xd20 net/ipv6/route.c:826 find_rr_leaf net/ipv6/route.c:847 [inline] rt6_select net/ipv6/route.c:891 [inline] fib6_table_lookup+0x649/0xa20 net/ipv6/route.c:2185 ip6_pol_route+0x1c5/0x11e0 net/ipv6/route.c:2221 pol_lookup_func include/net/ip6_fib.h:580 [inline] fib6_rule_lookup+0x52a/0x6f0 net/ipv6/fib6_rules.c:120 ip6_route_output_flags_noref+0x2e2/0x380 net/ipv6/route.c:2629 ip6_route_output_flags+0x72/0x320 net/ipv6/route.c:2642 ip6_route_output include/net/ip6_route.h:98 [inline] ip6_dst_lookup_tail+0x5ab/0x1620 net/ipv6/ip6_output.c:1070 ip6_dst_lookup_flow+0x8c/0x1d0 net/ipv6/ip6_output.c:1200 geneve_get_v6_dst+0x46f/0x9a0 drivers/net/geneve.c:858 geneve6_xmit_skb drivers/net/geneve.c:991 [inline] geneve_xmit+0x520/0x3530 drivers/net/geneve.c:1074 __netdev_start_xmit include/linux/netdevice.h:4685 [inline] netdev_start_xmit include/linux/netdevice.h:4699 [inline] xmit_one net/core/dev.c:3473 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3489 __dev_queue_xmit+0x2983/0x3640 net/core/dev.c:4112 neigh_resolve_output net/core/neighbour.c:1522 [inline] neigh_resolve_output+0x50e/0x820 net/core/neighbour.c:1502 neigh_output include/net/neighbour.h:541 [inline] ip6_finish_output2+0x56e/0x14f0 net/ipv6/ip6_output.c:126 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline] __ip6_finish_output+0x61e/0xe80 net/ipv6/ip6_output.c:170 ip6_finish_output+0x32/0x200 net/ipv6/ip6_output.c:201 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:224 dst_output include/net/dst.h:451 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ndisc_send_skb+0xa99/0x17f0 net/ipv6/ndisc.c:508 ndisc_send_rs+0x12e/0x6f0 net/ipv6/ndisc.c:702 addrconf_rs_timer+0x3f2/0x820 net/ipv6/addrconf.c:3898 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:unwind_next_frame+0xdeb/0x1ce0 arch/x86/kernel/unwind_orc.c:593 Code: 85 75 0d 00 00 83 e1 07 38 c8 0f 9e c2 84 c0 0f 95 c0 84 c2 0f 85 60 0d 00 00 41 0f b6 40 04 c0 e8 04 3c 01 0f 84 98 05 00 00 <3c> 04 74 21 84 c0 0f 84 b6 00 00 00 80 3d 86 bf 49 0c 00 0f b6 f0 RSP: 0018:ffffc9000291f6b0 EFLAGS: 00000297 RAX: 0000000000000000 RBX: 1ffff92000523ede RCX: 0000000000000001 RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffc9000291f7e0 RBP: 0000000000000001 R08: ffffffff8e199f54 R09: 0000000000000001 R10: fffff52000523efc R11: 000000000008808a R12: ffffc9000291fae8 R13: ffffc9000291f7bd R14: ffffc9000291f788 R15: ffffffff8e199f58 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:236 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3510 [inline] kfree+0xd0/0x4b0 mm/slub.c:4561 tipc_group_delete+0x2ff/0x450 net/tipc/group.c:229 tipc_sk_leave net/tipc/socket.c:3115 [inline] tipc_release+0x1f4/0x1a80 net/tipc/socket.c:643 __sock_release+0xcd/0x280 net/socket.c:649 sock_close+0x18/0x20 net/socket.c:1314 __fput+0x286/0x9f0 fs/file_table.c:311 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f0de6db6e99 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0de572c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000124 RAX: 0000000000000003 RBX: 00007f0de6ec9f60 RCX: 00007f0de6db6e99 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000004 RBP: 00007f0de6e10ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff3968b39f R14: 00007f0de572c300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 85 75 0d test %esi,0xd(%rbp) 3: 00 00 add %al,(%rax) 5: 83 e1 07 and $0x7,%ecx 8: 38 c8 cmp %cl,%al a: 0f 9e c2 setle %dl d: 84 c0 test %al,%al f: 0f 95 c0 setne %al 12: 84 c2 test %al,%dl 14: 0f 85 60 0d 00 00 jne 0xd7a 1a: 41 0f b6 40 04 movzbl 0x4(%r8),%eax 1f: c0 e8 04 shr $0x4,%al 22: 3c 01 cmp $0x1,%al 24: 0f 84 98 05 00 00 je 0x5c2 * 2a: 3c 04 cmp $0x4,%al <-- trapping instruction 2c: 74 21 je 0x4f 2e: 84 c0 test %al,%al 30: 0f 84 b6 00 00 00 je 0xec 36: 80 3d 86 bf 49 0c 00 cmpb $0x0,0xc49bf86(%rip) # 0xc49bfc3 3d: 0f b6 f0 movzbl %al,%esi