INFO: task systemd-udevd:28442 blocked for more than 143 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-udevd state:D stack:25088 pid:28442 ppid: 2969 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6382 __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 btrfs_control_ioctl+0x115/0x2d0 fs/btrfs/super.c:2411 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f3b418cb017 RSP: 002b:00007ffd4252a318 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3b418cb017 RDX: 00007ffd4252a330 RSI: 0000000090009427 RDI: 0000000000000010 RBP: 00007ffd4252a330 R08: 0000000000000000 R09: 00007f3b41917d90 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000010 R13: 0000000000000000 R14: 00005641757f7cf0 R15: 00005641757e4980 INFO: task systemd-udevd:28526 blocked for more than 143 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-udevd state:D stack:25088 pid:28526 ppid: 2969 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6382 __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 btrfs_control_ioctl+0x115/0x2d0 fs/btrfs/super.c:2411 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f3b418cb017 RSP: 002b:00007ffd4252a318 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3b418cb017 RDX: 00007ffd4252a330 RSI: 0000000090009427 RDI: 000000000000000f RBP: 00007ffd4252a330 R08: 0000000000000000 R09: 00007f3b41917d90 R10: 0000000000000001 R11: 0000000000000246 R12: 000000000000000f R13: 0000000000000000 R14: 00005641757e47c0 R15: 00005641757e4980 INFO: task systemd-udevd:28583 blocked for more than 143 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-udevd state:D stack:25088 pid:28583 ppid: 2969 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6382 __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 btrfs_control_ioctl+0x115/0x2d0 fs/btrfs/super.c:2411 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f3b418cb017 RSP: 002b:00007ffd4252a318 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3b418cb017 RDX: 00007ffd4252a330 RSI: 0000000090009427 RDI: 000000000000000f RBP: 00007ffd4252a330 R08: 0000000000000000 R09: 00007f3b41917d90 R10: 0000000000000001 R11: 0000000000000246 R12: 000000000000000f R13: 0000000000000000 R14: 00005641757e47c0 R15: 00005641757e4980 INFO: task systemd-udevd:31053 blocked for more than 143 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-udevd state:D stack:25088 pid:31053 ppid: 2969 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6382 __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 blkdev_get_by_dev+0x6b/0x80 block/bdev.c:859 blkdev_open+0x154/0x2e0 block/fops.c:501 do_dentry_open+0x4c8/0x1250 fs/open.c:822 do_open fs/namei.c:3426 [inline] path_openat+0x1cad/0x2750 fs/namei.c:3559 do_filp_open+0x1aa/0x400 fs/namei.c:3586 do_sys_openat2+0x16d/0x4d0 fs/open.c:1212 do_sys_open fs/open.c:1228 [inline] __do_sys_open fs/open.c:1236 [inline] __se_sys_open fs/open.c:1232 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1232 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f3b41b99840 RSP: 002b:00007ffd42530668 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00005641757e4570 RCX: 00007f3b41b99840 RDX: 0000564173d51fe3 RSI: 00000000000a0800 RDI: 00005641757e4530 RBP: 00007ffd425307e0 R08: 0000564173d51670 R09: 0000000000000010 R10: 00007f3b41913d70 R11: 0000000000000246 R12: 00007ffd42530730 R13: 00005641757f6060 R14: 0000000000000003 R15: 000000000000000e INFO: task syz-executor.5:15723 blocked for more than 144 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:26296 pid:15723 ppid: 16200 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178 __loop_clr_fd+0x1ae/0x1070 drivers/block/loop.c:1122 lo_release+0x1ac/0x1f0 drivers/block/loop.c:1761 blkdev_put_whole block/bdev.c:694 [inline] blkdev_put+0x2fb/0x9e0 block/bdev.c:956 btrfs_close_bdev fs/btrfs/volumes.c:1114 [inline] btrfs_close_bdev fs/btrfs/volumes.c:1104 [inline] btrfs_close_one_device fs/btrfs/volumes.c:1135 [inline] close_fs_devices+0x24f/0xa60 fs/btrfs/volumes.c:1178 btrfs_close_devices+0x8e/0x4b0 fs/btrfs/volumes.c:1193 open_ctree+0x48af/0x4954 fs/btrfs/disk-io.c:3700 btrfs_fill_super fs/btrfs/super.c:1359 [inline] btrfs_mount_root.cold+0x15/0x162 fs/btrfs/super.c:1726 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 fc_mount fs/namespace.c:994 [inline] vfs_kern_mount.part.0+0xd3/0x170 fs/namespace.c:1024 vfs_kern_mount+0x3c/0x60 fs/namespace.c:1011 btrfs_mount+0x234/0xa60 fs/btrfs/super.c:1786 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 do_new_mount fs/namespace.c:2988 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3318 do_mount fs/namespace.c:3331 [inline] __do_sys_mount fs/namespace.c:3539 [inline] __se_sys_mount fs/namespace.c:3516 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3516 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fd4791cb01a RSP: 002b:00007fd47673efa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007fd4791cb01a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007fd47673f000 RBP: 00007fd47673f040 R08: 00007fd47673f040 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000 R13: 0000000020000100 R14: 00007fd47673f000 R15: 00000000200012c0 INFO: task syz-executor.1:15782 blocked for more than 144 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:27664 pid:15782 ppid: 7351 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6382 __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 btrfs_mount_root+0x23b/0xc10 fs/btrfs/super.c:1681 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 fc_mount fs/namespace.c:994 [inline] vfs_kern_mount.part.0+0xd3/0x170 fs/namespace.c:1024 vfs_kern_mount+0x3c/0x60 fs/namespace.c:1011 btrfs_mount+0x234/0xa60 fs/btrfs/super.c:1786 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 do_new_mount fs/namespace.c:2988 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3318 do_mount fs/namespace.c:3331 [inline] __do_sys_mount fs/namespace.c:3539 [inline] __se_sys_mount fs/namespace.c:3516 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3516 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f93da8d101a RSP: 002b:00007f93d7e44fa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f93da8d101a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f93d7e45000 RBP: 00007f93d7e45040 R08: 00007f93d7e45040 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000 R13: 0000000020000100 R14: 00007f93d7e45000 R15: 00000000200012c0 INFO: task syz-executor.3:15793 blocked for more than 144 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:27664 pid:15793 ppid: 12751 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6382 __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 btrfs_mount_root+0x23b/0xc10 fs/btrfs/super.c:1681 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 fc_mount fs/namespace.c:994 [inline] vfs_kern_mount.part.0+0xd3/0x170 fs/namespace.c:1024 vfs_kern_mount+0x3c/0x60 fs/namespace.c:1011 btrfs_mount+0x234/0xa60 fs/btrfs/super.c:1786 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 do_new_mount fs/namespace.c:2988 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3318 do_mount fs/namespace.c:3331 [inline] __do_sys_mount fs/namespace.c:3539 [inline] __se_sys_mount fs/namespace.c:3516 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3516 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f1b3509001a RSP: 002b:00007f1b32603fa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f1b3509001a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f1b32604000 RBP: 00007f1b32604040 R08: 00007f1b32604040 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000 R13: 0000000020000100 R14: 00007f1b32604000 R15: 00000000200012c0 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8b983b60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 1 lock held by in:imklog/6212: 4 locks held by rs:main Q:Reg/6213: #0: ffff888073385770 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 #1: ffff888022b30460 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x12d/0x250 fs/read_write.c:643 #2: ffff888022b32bd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x1ab/0x690 mm/page-writeback.c:2364 #3: ffff888075902060 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x5e1/0x17d0 fs/ext4/inode.c:630 2 locks held by agetty/6444: #0: ffff88807b157098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc90002a9c2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 1 lock held by systemd-udevd/28442: #0: ffffffff8c065448 (uuid_mutex){+.+.}-{3:3}, at: btrfs_control_ioctl+0x115/0x2d0 fs/btrfs/super.c:2411 1 lock held by systemd-udevd/28526: #0: ffffffff8c065448 (uuid_mutex){+.+.}-{3:3}, at: btrfs_control_ioctl+0x115/0x2d0 fs/btrfs/super.c:2411 1 lock held by systemd-udevd/28583: #0: ffffffff8c065448 (uuid_mutex){+.+.}-{3:3}, at: btrfs_control_ioctl+0x115/0x2d0 fs/btrfs/super.c:2411 1 lock held by systemd-udevd/31053: #0: ffff88801a7a9918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 2 locks held by kworker/u4:2/32285: #0: ffff8880b9c39a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:478 #1: ffff8880b9c279c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x3a6/0x490 kernel/sched/psi.c:880 4 locks held by syz-executor.5/15723: #0: ffff8880753940e0 (&type->s_umount_key#92/1){+.+.}-{3:3}, at: alloc_super+0x1dd/0xac0 fs/super.c:229 #1: ffffffff8c065448 (uuid_mutex){+.+.}-{3:3}, at: btrfs_close_devices+0x86/0x4b0 fs/btrfs/volumes.c:1192 #2: ffff88801a7a9918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x97/0x9e0 block/bdev.c:914 #3: ffff88801a695360 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x7a/0x1070 drivers/block/loop.c:1106 1 lock held by syz-executor.1/15782: #0: ffffffff8c065448 (uuid_mutex){+.+.}-{3:3}, at: btrfs_mount_root+0x23b/0xc10 fs/btrfs/super.c:1681 1 lock held by syz-executor.3/15793: #0: ffffffff8c065448 (uuid_mutex){+.+.}-{3:3}, at: btrfs_mount_root+0x23b/0xc10 fs/btrfs/super.c:1681 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-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 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:295 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 32285 Comm: kworker/u4:2 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:check_kcov_mode kernel/kcov.c:166 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x1c/0x60 kernel/kcov.c:200 Code: be b0 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 65 8b 05 09 89 8a 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 40 70 02 00 00 01 ff 00 74 0e 85 c9 74 35 8b 82 a4 15 00 00 85 c0 74 2b 8b RSP: 0018:ffffc9000521fa18 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888020e99d00 RSI: ffffffff817e2ae1 RDI: 0000000000000003 RBP: ffffffff893dc540 R08: 0000000000000000 R09: ffffffff9054b01b R10: ffffffff817e2ad8 R11: 0000000000000000 R12: ffffc9000521fb88 R13: 1ffff92000a43f5a R14: ffffffff9054b018 R15: ffffffff9054b010 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7312e06020 CR3: 000000000b68e000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: trace_hardirqs_on+0x41/0x1c0 kernel/trace/trace_preemptirq.c:45 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x50/0x70 kernel/locking/spinlock.c:194 __debug_object_init+0x409/0xd10 lib/debugobjects.c:605 init_timer_on_stack_key kernel/time/timer.c:752 [inline] schedule_timeout+0xf2/0x2a0 kernel/time/timer.c:1879 toggle_allocation_gate mm/kfence/core.c:739 [inline] toggle_allocation_gate+0x305/0x390 mm/kfence/core.c:724 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: be b0 01 00 00 mov $0x1b0,%esi 5: e8 b4 ff ff ff callq 0xffffffbe a: 31 c0 xor %eax,%eax c: c3 retq d: 90 nop e: 65 8b 05 09 89 8a 7e mov %gs:0x7e8a8909(%rip),%eax # 0x7e8a891e 15: 89 c1 mov %eax,%ecx 17: 48 8b 34 24 mov (%rsp),%rsi 1b: 81 e1 00 01 00 00 and $0x100,%ecx 21: 65 48 8b 14 25 40 70 mov %gs:0x27040,%rdx 28: 02 00 * 2a: a9 00 01 ff 00 test $0xff0100,%eax <-- trapping instruction 2f: 74 0e je 0x3f 31: 85 c9 test %ecx,%ecx 33: 74 35 je 0x6a 35: 8b 82 a4 15 00 00 mov 0x15a4(%rdx),%eax 3b: 85 c0 test %eax,%eax 3d: 74 2b je 0x6a 3f: 8b .byte 0x8b