INFO: task syz.4.21:6056 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.21 state:D stack:28192 pid:6056 tgid:6054 ppid:5933 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145f/0x5070 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244 inode_lock include/linux/fs.h:1027 [inline] ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 iter_file_splice_write+0x977/0x10b0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x104/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5b3/0xcd0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x187/0x270 fs/splice.c:1230 do_sendfile+0x4ec/0x7f0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe4601df749 RSP: 002b:00007fe45f825038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fe460436090 RCX: 00007fe4601df749 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000005 RBP: 00007fe460263f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000e3aa6ea R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe460436128 R14: 00007fe460436090 R15: 00007ffea40a5818 INFO: task syz.3.22:6068 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.22 state:D stack:28272 pid:6068 tgid:6063 ppid:5928 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145f/0x5070 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244 inode_lock include/linux/fs.h:1027 [inline] ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 iter_file_splice_write+0x977/0x10b0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x104/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5b3/0xcd0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x187/0x270 fs/splice.c:1230 do_sendfile+0x4ec/0x7f0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f40c396f749 RSP: 002b:00007f40c2fb5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f40c3bc6090 RCX: 00007f40c396f749 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000005 RBP: 00007f40c39f3f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000e3aa6ea R11: 0000000000000246 R12: 0000000000000000 R13: 00007f40c3bc6128 R14: 00007f40c3bc6090 R15: 00007ffda4f56388 INFO: task syz.0.17:6070 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:28184 pid:6070 tgid:6065 ppid:5919 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145f/0x5070 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244 inode_lock include/linux/fs.h:1027 [inline] ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 iter_file_splice_write+0x977/0x10b0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x104/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5b3/0xcd0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x187/0x270 fs/splice.c:1230 do_sendfile+0x4ec/0x7f0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7fd2c2f749 RSP: 002b:00007f7fd227d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f7fd2e86090 RCX: 00007f7fd2c2f749 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000005 RBP: 00007f7fd2cb3f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000e3aa6ea R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7fd2e86128 R14: 00007f7fd2e86090 R15: 00007ffd6f145638 INFO: task syz.2.19:6078 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.19 state:D stack:28280 pid:6078 tgid:6074 ppid:5927 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145f/0x5070 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244 inode_lock include/linux/fs.h:1027 [inline] ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 iter_file_splice_write+0x977/0x10b0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x104/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5b3/0xcd0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x187/0x270 fs/splice.c:1230 do_sendfile+0x4ec/0x7f0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f60fc19f749 RSP: 002b:00007f60fb7ed038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f60fc3f6090 RCX: 00007f60fc19f749 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000005 RBP: 00007f60fc223f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000e3aa6ea R11: 0000000000000246 R12: 0000000000000000 R13: 00007f60fc3f6128 R14: 00007f60fc3f6090 R15: 00007ffc89a23998 INFO: task syz.1.18:6079 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.18 state:D stack:28280 pid:6079 tgid:6076 ppid:5922 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145f/0x5070 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244 inode_lock include/linux/fs.h:1027 [inline] ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 iter_file_splice_write+0x977/0x10b0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x104/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5b3/0xcd0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x187/0x270 fs/splice.c:1230 do_sendfile+0x4ec/0x7f0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4110ddf749 RSP: 002b:00007f411042d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f4111036090 RCX: 00007f4110ddf749 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000005 RBP: 00007f4110e63f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000e3aa6ea R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4111036128 R14: 00007f4111036090 R15: 00007ffcb4327368 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 7 locks held by kworker/u8:6/145: 2 locks held by getty/5564: #0: ffff888034c550a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211 2 locks held by syz.4.21/6055: 2 locks held by syz.4.21/6056: #0: ffff8880381d4480 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff888048a85838 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff888048a85838 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 3 locks held by syz.3.22/6064: 2 locks held by syz.3.22/6068: #0: ffff88805974c480 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff88802fe62268 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff88802fe62268 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 2 locks held by syz.0.17/6066: 2 locks held by syz.0.17/6070: #0: ffff88802790c480 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff88802fe62a18 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff88802fe62a18 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 2 locks held by syz.2.19/6075: 2 locks held by syz.2.19/6078: #0: ffff88802936a480 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff88802fe631c8 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff88802fe631c8 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 3 locks held by syz.1.18/6077: 2 locks held by syz.1.18/6079: #0: ffff888035474480 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff88805f4e2268 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff88805f4e2268 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 2 locks held by syz.5.23/6218: 2 locks held by syz.5.23/6219: #0: ffff888039138480 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff88802fe66f48 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff88802fe66f48 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 3 locks held by syz.9.27/6222: 2 locks held by syz.9.27/6226: #0: ffff888032e5a480 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff888048b2d838 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff888048b2d838 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 3 locks held by syz.6.24/6224: 2 locks held by syz.6.24/6228: #0: ffff888034baa480 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff888048cf9308 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff888048cf9308 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 3 locks held by syz.7.25/6230: 2 locks held by syz.7.25/6236: #0: ffff88806043c480 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff888048a2e798 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff888048a2e798 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 2 locks held by syz.8.28/6241: 2 locks held by syz.8.28/6242: #0: ffff8880281b6480 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff888021fed088 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff888021fed088 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284 6 locks held by kworker/u8:35/6424: 2 locks held by kworker/u8:38/6618: 4 locks held by syz.2.151/6656: 1 lock held by syz.4.153/6655: 5 locks held by syz.3.154/6657: 2 locks held by syz.1.152/6658: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400 Code: e8 9e f3 b5 fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 ef 29 18 fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 1a 99 cb 05 cc 44 89 f9 80 e1 07 RSP: 0018:ffffc90000167950 EFLAGS: 00000202 RAX: 1ffffffff31f3500 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff98f9aff0 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff8509b600 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff98f9ad60 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888126cef000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff6327c5e00 CR3: 0000000028116000 CR4: 00000000003526f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:128 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline] wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1961 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline] serial8250_console_write+0x11bd/0x1b40 drivers/tty/serial/8250/8250_port.c:3342 console_emit_next_record kernel/printk/printk.c:3109 [inline] console_flush_one_record+0x685/0xb80 kernel/printk/printk.c:3215 legacy_kthread_func+0x16f/0x210 kernel/printk/printk.c:3674 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246